Patent Application
20230180276
The present invention generally relates to wireless communication networks, and particularly relates to improvements to uplink (UL) transmissions by a wireless device to multiple transmission reception points (TRPs) in a wireless network for which the wireless device can select among multiple available transmission configurations.
Currently the fifth generation (“5G”) of cellular systems, also referred to as New Radio (NR), is being standardized within the Third-Generation Partnership Project (3GPP). NR is developed for maximum flexibility to support multiple and substantially different use cases. These include enhanced mobile broadband (eMBB), machine type communications (MTC), ultra-reliable low latency communications (URLLC), side-link device-to-device (D2D), and several other use cases. The present disclosure relates generally to NR, but the following description of Long-Term Evolution (LTE) technology is provided for context since it shares many features with NR.
LTE is an umbrella term for so-called fourth-generation (4G) radio access technologies developed within the Third-Generation Partnership Project (3GPP) and initially standardized in Release 8 (Rel-8) and Release 9 (Rel-9), also known as Evolved UTRAN (E-UTRAN). LTE is targeted at various licensed frequency bands and is accompanied by improvements to non-radio aspects commonly referred to as System Architecture Evolution (SAE), which includes Evolved Packet Core (EPC) network.
The LTE E-UTRAN includes one or more evolved Node B’s (eNB), each of which can serve one or more cells by which user equipment (UEs) communicate with the LTE network. As used within the 3GPP standards, “user equipment” or “UE” means any wireless communication device (e.g., smartphone or computing device) that is capable of communicating with 3GPP-standard-compliant network equipment, including E-UTRAN as well as UTRAN and/or GERAN, as the third-generation (“3G”) and second-generation (“2G”) 3GPP RANs are commonly known.
As specified by 3GPP, the E-UTRAN is responsible for all radio-related functions in the network, including radio bearer control, radio admission control, radio mobility control, scheduling, and dynamic allocation of resources to UEs in uplink (UL, i.e., UE to E-UTRAN) and downlink (DL, i.e., E-UTRAN to UE), as well as security of the communications with the UE. In general, these functions reside in the respective eNBs, which communicate with each other via an X2 interface. The eNBs also are responsible for the E-UTRAN interface to the EPC, specifically an S1 interface to a Mobility Management Entity (MME) and a Serving Gateway (SGW). In general, the MME/S-GW handles both the overall control of the UE and data flow between the UE and the rest of the EPC. More specifically, the MME processes the signaling (e.g., control plane, CP) protocols between the UE and the EPC, which are known as the Non-Access Stratum (NAS) protocols. The S-GW handles all Internet Protocol (IP) data packets (e.g., user plane, UP) between the UE and the EPC and serves as the local mobility anchor for the data bearers when the UE moves between eNBs.
The RRC layer controls communications between a UE and an eNB at the radio interface, as well as the mobility of a UE between cells in the E-UTRAN. After a UE is powered ON it will be in the RRC_IDLE state until an RRC connection is established with the network, at which time the UE will transition to RRC_CONNECTED state (e.g., where data transfer can occur). The UE returns to RRC_IDLE after the connection with the network is released. In RRC_ IDLE state, the UE does not belong to any cell, no RRC context has been established for the UE (e.g., in E-UTRAN), and the UE is out of UL synchronization with the network. Even so, a UE in RRC_IDLE state is known in the EPC and has an assigned IP address.
Furthermore, in RRC_IDLE state, the UE’s radio is active on a discontinuous reception (DRX) schedule configured by upper layers. During DRX active periods (also referred to as “DRX On durations”), an RRC_IDLE UE receives system information (SI) broadcast by a serving cell, performs measurements of neighbor cells to support cell reselection, and monitors a paging channel for pages from the EPC via an eNB serving the cell in which the UE is camping. A UE must perform a random-access (RA) procedure to move from RRC_IDLE to RRC_CONNECTED state. In RRC_CONNECTED state, the cell serving the UE is known and an RRC context is established for the UE in the serving eNB, such that the UE and eNB can communicate. For example, a Cell Radio Network Temporary Identifier (C-RNTI) — a UE identity used for signaling between UE and network — is configured for a UE in RRC_CONNECTED state.
The multiple access scheme for the LTE PHY is based on Orthogonal Frequency Division Multiplexing (OFDM) with a cyclic prefix (CP) in the DL, and on Single-Carrier Frequency Division Multiple Access (SC-FDMA) with a cyclic prefix in the UL. To support transmission in paired and unpaired spectrum, the LTE PHY supports both Frequency Division Duplexing (FDD) (including both full- and half-duplex operation) and Time Division Duplexing (TDD). A combination of a particular subcarrier in a particular symbol is known as a resource element (RE). Each RE is used to transmit a particular number of bits, depending on the type of modulation and/or bit-mapping constellation used for that RE. The radio resources of the LTE PHY are also defined in terms of physical resource blocks (PRBs). Each PRB spans NRBscsub-carriers over the duration of a slot (i.e., NDLsymb or NDLsymb symbols), where NRBsc is typically either 12 or 24.
In general, an LTE physical channel corresponds to a set of REs carrying information that originates from higher layers. DL physical channels include Physical Downlink Shared Channel (PDSCH), Physical Downlink Control Channel (PDCCH), Physical Broadcast Channel (PBCH), etc. PDSCH is the main physical channel used for unicast DL data transmission, but also for transmission of RAR (random access response), certain SI blocks, and paging information. PBCH carries the basic SI required by the UE to access the network. PDCCH is used for transmitting downlink control information (DCI) including scheduling information for DL transmissions on PDSCH, grants for UL transmission on PUSCH, and channel quality feedback (e.g., CSI) for the UL channel.
UL physical channels include Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), and Physical Random-Access Channel (PRACH). PUSCH is the UL counterpart to the PDSCH. PUCCH is used by UEs to transmit uplink control information (UCI) including HARQ feedback for eNB DL transmissions, channel quality feedback (e.g., CSI) for the DL channel, scheduling requests (SRs), etc. PRACH is used for random access preamble transmission.
In addition, the LTE PHY includes various DL and UL reference signals, synchronization signals, and discovery signals. For example, demodulation reference signals (DM-RS) are transmitted in the DL (UL) to aid the UE (eNB) in the reception of an associated PDCCH (PUCCH) or PDSCH (PUSCH). Channel state information reference signals (CSI-RS) are transmitted in the DL to enable channel quality feedback by a UE. Sounding reference signals (SRS) are transmitted by UEs and enable the eNB to determine UL channel quality.
UL and DL data transmissions (e.g., on PUSCH and PDSCH, respectively) can take place with or without an explicit grant or assignment of resources by the network (e.g., eNB). In general, UL transmissions are usually referred to as being “granted” by the network (i.e., “UL grant”), while DL transmissions are usually referred to as taking place on resources that are “assigned” by the network (i.e., “DL assignment”). For transmission based on an explicit grant/assignment, DCI informs the UE of radio resources to use for UL transmission/DL reception. In contrast, a transmission/reception without an explicit grant/assignment is typically configured to occur with a defined periodicity according to a predefined configuration. Such transmissions can be referred to as semi-persistent scheduling (SPS), configured grant (CG), or grant-free transmissions.
Fifth generation (5G) NR technology shares many similarities with fourth-generation LTE. For example, NR uses CP-OFDM (Cyclic Prefix Orthogonal Frequency Division Multiplexing) in the DL and both CP-OFDM and DFT-spread OFDM (DFT-S-OFDM) in the UL. As another example, in the time domain, NR DL and UL physical resources are organized into equal-sized 1-ms subframes. A subframe is further divided into multiple slots of equal duration, with each slot including multiple OFDM-based symbols. As another example, NR RRC layer includes RRC_IDLE and RRC_CONNECTED states, but adds an additional state known as RRC_INACTIVE, which has some properties similar to a “suspended” condition used in LTE.
In addition to providing coverage via “cells,” as in LTE, NR networks also provide coverage via “beams.” In general, a DL “beam” is a coverage area of a network-transmitted RS that may be measured or monitored by a UE. In NR, for example, such RS can include any of the following: SS/PBCH block (SSB), CSI-RS, tertiary reference signals (or any other sync signal), positioning RS (PRS), demodulation reference signal (DMRS), phase-tracking reference signals (PTRS), etc. In general, SSB is available to UEs in any RRC state, while other RS (e.g., CSI-RS, DM-RS, PTRS) are associated with specific UEs that have a network connection, i.e., in RRC_CONNECTED state.
NR uses two types of UL CGs. Type-1 are configured via RRC signaling only. For Type-2, some parameters are preconfigured via RRC signaling and some parameters are configured via MAC. The RRC configuration of a UL CG includes a configuredGrantTimer value used for controlling UL hybrid ARQ (HARQ) processes via a “CG timer” in the UE. The related feature of Autonomous Uplink (AUL) supports autonomous HARQ retransmissions using an UL CG.
Each NR base station (also referred to as “gNB”) may include and/or be associated with a plurality of Transmission Reception Points (TRPs). Each TRP is typically an antenna array with one or more antenna elements and is located at a specific geographical location. In this manner, a gNB associated with multiple TRPs can transmit the same or different signals from each of the TRPs. For example, a gNB can transmit different version of the same signal on multiple TRPs to a single UE. Each of the TRPs can also employ beams for transmission and reception towards the UEs served by the gNB, as briefly mentioned above.
Transmitting data to multiple, spatially separated TRPs can improve the reliability of UL transmissions, which can be important for 5G services such as URLLC. Even so, there are various problems, issues, and/or difficulties related to using UL CGs for UE transmissions to multiple TRPs. These require solutions so that the reliability advantages of using multiple TRPs can be realized in 5G deployments.
Embodiments of the present disclosure provide specific improvements to communication between user equipment (UE) and network nodes in a wireless communication network, such as by facilitating solutions to overcome the exemplary problems summarized above and described in more detail below.
Some embodiments include methods (e.g., procedures) for UL transmission of data to a plurality of TRPs in a wireless network (e.g., E-UTRAN, NG-RAN). These exemplary methods can be performed by a UE (e.g., wireless device, IoT device, modem, etc. or component thereof).
These exemplary methods can include receiving, from the wireless network, configurations for a plurality of configured grants of resources for UL transmission (UL CGs). At least one of the UL CG configurations can include resources for transmission to a plurality of TRPs. These exemplary methods can also include selecting one or more of the UL CG configurations for transmission of data available at the UE based on characteristics of the data and/or of radio channels between the UE and the respective TRPs. These exemplary methods can also include transmitting the data to one or more of the plurality of TRPs on resources of the selected one or more UL CG configurations.
In some embodiments, the characteristics associated with the radio channel include radio channel quality. In such embodiments, these exemplary methods can also include determining respective radio channel qualities between the UE and the respective TRPs according to one or more of various metrics described herein. Alternately, these exemplary methods can include receiving indications of the respective radio channel qualities from the wireless network.
In some embodiments, the characteristics associated with the radio channel can include latency characteristics. In some embodiments, the characteristics associated with the data can include amount, arrival rate, arrival time, type of service, latency requirements, and reliability requirements.
In some embodiments, each UL CG configuration identifies a plurality of transmission opportunities. In such embodiments, the selecting operations can include selecting an UL CG configuration based on arrival time of the data relative to the transmission opportunities identified by the respective UL CG configurations.
In some embodiments, the resources of the UL CGs can be associated with respective modulation and coding schemes (MCS). In such embodiments, the selecting operations can include selecting an UL CG configuration that includes resources associated with one of the following: highest capacity MCS, or most reliable MCS.
In some embodiments, the data comprises a transport block (TB). In such embodiments, each UL CG configuration identifies a particular number of TRPs and respective numbers of repetitions of the TB to be transmitted to the respective ones of the particular number of TRPs.
In some of these embodiments, the one or more repetitions are a single repetition. In such embodiments, the selecting operations can include selecting an UL CG configuration that includes resources associated with the TRP having the best radio channel quality towards the UE. In such embodiments, the transmitting operations can include transmitting the single repetition of the TB to the TRP having the best radio channel quality towards the UE.
In other of these embodiments, the one or more repetitions include a plurality of repetitions. In such embodiments, first and second UL CG configurations are selected, and the transmitting operations include transmitting a first portion of the plurality of repetitions on resources of the first UL CG configuration and transmitting a second portion of the plurality of repetitions on resources of the second UL CG configuration.
In other of these embodiments, the plurality of UL CG configurations can include a first UL CG configuration that identifies a first TRP to which all repetitions of the TB are transmitted, and a second UL CG configuration that identifies the first TRP and a first number of repetitions and a second TRP and a second number of repetitions. In such embodiments, when the first UL CG configuration is selected, the UE transmits respective repetitions of the TB to the first TRP in respective transmission opportunities. Likewise, when the second UL CG configuration is selected, the UE transmits at least one of the first number of repetitions to the first TRP concurrently with at least one of the second number of repetitions to the second TRP in one or more of the transmission opportunities.
As a more detailed example of such embodiments, one of the following first conditions applies for each of the one or more transmission opportunities: a single repetition of the first number is transmitted to the first TRP; or a plurality of the first number are transmitted to the first TRP in a respective plurality of frequency regions. In addition, one of the following second conditions applies for each of the one or more transmission opportunities: a single repetition of the second number is transmitted to the second TRP; or a plurality of the second number are transmitted to the second TRP in the respective plurality of frequency regions.
In some embodiments, the data comprises a transport block (TB) associated with a HARQ process. In such embodiments, first and second UL CG configurations are selected, and the transmitting operations include transmitting an initial transmission of the TB on resources of the first UL CG configuration and transmitting at least one retransmission of the TB on resources of the second UL CG configuration. In some of these embodiments, the resources of the first UL CG configuration are associated with a first TRP and the resources of the second UL CG configuration are associated with a second TRP. In this manner, the initial transmission (and the at least one retransmission can be transmitted to different TRPs.
In some embodiments, these exemplary methods can also include receiving, from the wireless network, an indication that different UL CG configurations can be selected for transmission and retransmission in a single HARQ process.
Other embodiments include methods (e.g., procedures) for receiving UL transmission of data (e.g., by a UE) via a plurality of TRPs. These exemplary methods can be performed by a network node (e.g., base station, eNB, gNB, ng-eNB, etc., or components thereof) in a wireless network (e.g., E-UTRAN, NG-RAN).
These exemplary methods can include transmitting, to a UE, configurations for a plurality of configured grants of resources for UL transmission (UL CGs). At least one of the UL CG configurations can include resources for transmission to a plurality of TRPs. These exemplary methods can also include receiving UL data, from the UE via one or more of the plurality of TRPs, on resources of the one or more of the UL CG configurations that were selected by the UE, e.g., in any of the ways summarized above.
In some embodiments, these exemplary methods can also include determine respective radio channel qualities between the UE and the respective TRPs according to one or more metrics (described in more detail herein); and transmitting indications of the determined radio channel qualities to the UE.
In some embodiments, each UL CG configuration identifies a plurality of transmission opportunities. In such embodiments, the selected UL CG (e.g., by the UE in relation to the data received) is related to arrival time of the data at the UE relative to the transmission opportunities identified by the respective UL CG configurations.
In some embodiments, the resources of the UL CGs can be associated with respective modulation and coding schemes (MCS). In such embodiments, the selected UL CG includes resources associated with one of the following: highest capacity MCS, or most reliable MCS.
In some embodiments, the data comprises a transport block (TB). In such embodiments, each UL CG configuration identifies a particular number of TRPs and respective numbers of repetitions of the TB to be transmitted by the UE to respective ones of the particular number of TRPs.
In some of these embodiments, the one or more repetitions are a single repetition the one or more repetitions are a single repetition. In such embodiments, the receiving operations include receiving the single repetition of the TB via the TRP having the best radio channel quality towards the UE (e.g., as selected by the UE).
In other of these embodiments, the one or more repetitions include a plurality of repetitions. In such embodiments, the receiving operations can include receiving a first portion of the plurality of repetitions on resources of a first UL CG configuration and receiving a second portion of the plurality of repetitions on resources of a second UL CG configuration.
In other of these embodiments, the plurality of UL CG configurations can include a first UL CG configuration that identifies a first TRP to which all repetitions are transmitted, and a second UL CG configuration that identifies the first TRP and a first number of repetitions and a second TRP and a second number of repetitions. In such embodiments, the receiving operations can include one of the following: when the first UL CG configuration is selected, receiving respective repetitions of the TB via the first TRP in respective transmission opportunities; or when the second UL CG configuration is selected, receiving at least one of the first number of repetitions via the first TRP concurrently with at least one of the second number of repetitions via the second TRP in one or more of the transmission opportunities.
As a more detailed example of such embodiments, one of the following first conditions applies for each of the one or more transmission opportunities: a single repetition of the first number is received via the first TRP; or a plurality of the first number are received via the first TRP in a respective plurality of frequency regions. In addition, one of the following second conditions applies for each of the one or more transmission opportunities: a single repetition of the second number is received via the second TRP; or a plurality of the second number are received via the second TRP in the respective plurality of frequency regions.
In some embodiments, the data comprises a transport block (TB) associated with a hybrid ARQ (HARQ) process. In such embodiments, the receiving operations can include receiving an initial transmission of the TB on resources of the first UL CG configuration and receiving at least one retransmission of the TB on resources of the second UL CG configuration. In some of these embodiments, the resources of the first UL CG configuration are associated with a first TRP and the resources of the second UL CG configuration are associated with a second TRP. In this manner, the initial transmission and the at least one retransmission can be received via different TRPs.
In some of these embodiments, these exemplary methods can also include transmitting, to the UE, an indication that different UL CG configurations can be selected for transmission and retransmission in a single HARQ process. In such embodiments, the reception on resources of the second UL CG configuration can be based on this indication.
Other embodiments include UEs (e.g., wireless devices, IoT devices, etc. or components thereof) and network nodes (e.g., base stations, eNBs, gNBs, ng-eNBs, etc., or components thereof) configured to perform operations corresponding to any of the exemplary methods described herein. Other embodiments include non-transitory, computer-readable media storing program instructions that, when executed by processing circuitry, configure such UEs and network nodes to perform operations corresponding to any of the exemplary methods described herein.
These and other embodiments provide flexible and efficient techniques for a UE to select among a plurality of multi-TRP configurations available for transmission in relation to an UL CG based on various factors such as UL data for transmission at the UE, UE energy consumption, UL/DL radio channel conditions, etc. By selecting and utilizing multi-TRP configurations in this manner, a UE can reduce energy consumption and/or improve data transmission reliability and/or latency.
These and other objects, features, and advantages of embodiments of the present disclosure will become apparent upon reading the following Detailed Description in view of the Drawings briefly described below.
Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject matter disclosed herein, the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.
Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and/or is implied from the context in which it is used. All references to a/an/the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and/or where it is implicit that a step must follow or precede another step. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa. Other objectives, features, and advantages of the enclosed embodiments will be apparent from the following description.
Furthermore, the following terms are used throughout the description given below:
Note that the description herein focuses on a 3GPP cellular communications system and, as such, 3GPP terminology or terminology similar to 3GPP terminology is oftentimes used. However, the concepts disclosed herein are not limited to a 3GPP system. Furthermore, although the term “cell” is used herein, it should be understood that (particularly with respect to 5G NR) beams may be used instead of cells and, as such, concepts described herein apply equally to both cells and beams.
As briefly mentioned above, transmitting data to multiple, spatially separated TRPs can improve the reliability of UL transmissions, which can be important for 5G services such as URLLC. Even so, there are various problems, issues, and/or difficulties with respect to using UL CGs for UE transmissions to multiple TRPs. These are discussed in more detail after the following the introduction to 5G/NR networks.
NG-RAN 299 is layered into a Radio Network Layer (RNL) and a Transport Network Layer (TNL). The NG-RAN architecture, i.e., the NG-RAN logical nodes and interfaces between them, is defined as part of the RNL. For each NG-RAN interface (NG, Xn, F1) the related TNL protocol and the functionality are specified. The TNL provides services for user plane transport and signaling transport. In some exemplary configurations, each gNB is connected to all 5GC nodes within an “AMF Region,” which is defined in 3GPP TS 23.501. If security protection for CP and UP data on TNL of NG-RAN interfaces is supported, NDS/IP shall be applied.
The NG RAN logical nodes shown in
A gNB-CU connects to gNB-DUs over respective F1 logical interfaces, such as interfaces 222 and 232 shown in
Each of the gNBs 310 can support the NR radio interface including frequency division duplexing (FDD), time division duplexing (TDD), or a combination thereof. In contrast, each of ng-eNBs 320 can support the LTE radio interface but, unlike conventional LTE eNBs (such as shown in
Each of the gNBs 310 may include and/or be associated with a plurality of Transmission Reception Points (TRPs). Each TRP is typically an antenna array with one or more antenna elements and is located at a specific geographical location. In this manner, a gNB associated with multiple TRPs can transmit the same or different signals from each of the TRPs. For example, a gNB can transmit different version of the same signal on multiple TRPs to a single UE. Each of the TRPs can also employ beams for transmission and reception towards the UEs served by the gNB, as discussed above.
In multi-TRP operation, a UE receives from (or transmit to) multiple TRPs in the NG-RAN. Until NR Rel-16, the multiple transmissions were on a single carrier, such that all are associated with a single cell (as compared to CA that utilizes multiple carriers/cells). An important benefit of multi-TRP operation is reliability, which relates to the spatial diversity achieved by using different transmission paths to/from the respective TRPs. More specifically, multi-TRP diversity helps both in reducing blocking by obstacles (macro diversity) and in mitigation of fast fading due to combinations of signal reflections at the receiver. The basic principle of operation is transmitting multiple copies of the same data payload and combining them at the receiver to improve the receiver’s capability to recover the data payload.
In NR, PDCCH is confined to a region referred to as control resource set (CORESET). A CORESET includes multiple RBs (i.e., multiples of 12 REs) in the frequency domain and 1-3 OFDM symbols in the time domain, as further defined in 3GPP TS 38.211 § 7.3.2.2. A CORESET is functionally similar to the control region in an LTE subframe. In NR, however, each resource element group (REG) includes all 12 REs of one OFDM symbol in an RB, whereas an LTE REG includes only four REs. The CORESET time domain size can be configured by an RRC parameter. In LTE, the frequency bandwidth of the control region is fixed (i.e., to the total system bandwidth), whereas in NR, the frequency bandwidth of the CORESET is variable. CORESET resources can be indicated to a UE by RRC signaling.
Several signals can be transmitted from the same base station (e.g., gNB) antenna from different antenna ports. These signals can have the same large-scale properties, such as in terms of parameters including Doppler shift/spread, average delay spread, and/or average delay. These antenna ports are then said to be “quasi co-located” or “QCL”. The network can signal to the UE that two antenna ports are QCL with respect to one or more parameters. Once the UE knows that two antenna ports are QCL with respect to a certain parameter (e.g., Doppler spread), the UE can estimate that parameter based on one of the antenna ports and use that estimate when receiving the other antenna port. Typically, the first antenna port is represented by a measurement reference signal such as CSI-RS (referred to as “source RS”) and the second antenna port is a DMRS (referred to as “target RS”).
For instance, if antenna ports A and B are QCL with respect to average delay, the UE can estimate the average delay from the signal received from antenna port A (source RS) and assume that the signal received from antenna port B (target RS) has the same average delay. This can be useful for demodulation since the UE can know beforehand the properties of the channel when trying to measure the channel utilizing the DMRS.
Information about what assumptions can be made regarding QCL is signaled to the UE from the network. In NR, the following four types of QCL relations between a transmitted source RS and transmitted target RS are defined:
QCL Type D is the most relevant for beam management, but it is also necessary to convey a Type A QCL RS relation to UEs so they can estimate all the relevant large scale parameters. Typically, this can be done by configuring a UE with a tracking reference signal (TRS, e.g., a CSI-RS) for time/frequency offset estimation. To be able to use any QCL reference, the UE would have to receive it with a sufficiently good signal-to-interference-plus-noise ratio (SINR). In many cases, this constrains the TRS for a particular UE to be transmitted in a particular beam and/or beam configuration.
To introduce dynamics in beam and TRP selection, the UE can be configured through RRC signaling with N Transmission Configuration Indicator (TCI) states, where N is up to 128 in frequency range 2 (FR2, e.g., above 6 GHz) and up to eight in FR1 (e.g., below 6 GHz), depending on UE capability. Each configured TCI state includes parameters for the QCL associations between source RS (e.g., CSI-RS or SS/PBCH) and target RS (e.g., PDSCH/PDCCH DMRS antenna ports). TCI states can also be used to convey QCL information for the reception of CSI-RS. The N states in the list of TCI states can be interpreted as N possible beams transmitted by the network, or N possible TRPs used by the network to communicate with the UE.
More specifically, each TCI state can contain an ID along with QCL information for one or two source DL RSs, with each source RS associated with a QCL type, a serving cell index, a BWP index, and a source reference signal identity (CSI-RS, TRS or SSB). For example, two different CSI-RSs {CSI-RS1, CSI-RS2} can be configured in the TCI state as {qcl-Typel, qcl-Type2} = {Type A, Type D}. The UE can interpret this TCI state to mean that the UE can derive Doppler shift, Doppler spread, average delay, delay spread from CSI-RS 1, and Spatial Rx parameter (e.g., RX beam to use) from CSI-RS2. In case QCL Type D is not applicable (e.g., low- or mid-band operation), then a TCI state contains only a single source RS. Unless specifically noted, however, references to source RS “pairs” include cases of a single source RS.
Furthermore, a first list of available TCI states can be configured for PDSCH, and a second list can be configured for PDCCH. This second list can contain pointers, known as TCI State IDs, to a subset of the TCI states configured for PDSCH. For the UE operating in FR1, the network then activates one TCI state for PDCCH (i.e., by providing a TCI to the UE) and up to eight TCI states for PDSCH, depending on UE capability.
As an example, a UE can be configured with four active TCI states from a list of 64 total configured TCI states. Hence, the other 60 configured TCI states are inactive, and the UE need not be prepared to estimate large scale parameters for those. On the other hand, the UE continuously tracks and updates the large-scale parameters for the four active TCI states by performing measurements and analysis of the source RSs indicated for each of those four TCI states. Each DCI used for PDSCH scheduling includes a pointer (or index) to one or two active TCI states for the scheduled UE. Based on this pointer, the UE knows which large scale parameter estimate to use when performing PDSCH DMRS channel estimation and PDSCH demodulation.
The different values that can be represented by the pointer are referred to as “codepoints.” For example, a three-bit pointer field can represent up to eight TCI codepoints. Either one or two TCI states can be mapped to each TCI code point. When one TCI state is mapped to a TCI code point, the indicated TCI state is to be used for single-TRP transmission. When two TCI states are mapped to a TCI code point, the indicated TCI states are to be used for multi-TRP transmission.
Grouping of TCI states can be done through RRC or MAC CE signaling. In one option, TCI state sets are configured for PDSCH via RRC and each TCI state set contains one or two TCI states. MAC CE mechanism in Rel-15 is unchanged. In another option, TCI states are configured for PDSCH via RRC, as in Rel-15. Moreover, TCI states are selected by enhanced MAC CE indication mechanism whereby one or two TCI states can be activated for (e.g., to be associated with) each TCI code point in DCI.
Multi-TRP operation for PDSCH and/or PDCCH has been identified as an area for further enhancements to support more strict requirements on latency, reliability, and/or robustness for URLLC. For PDCCH, the same DCI is repeated across multiple CORESETs since each CORESET is configured with an individual TCI state. By this repetition, the UE can perform soft combining of the N PDCCH candidates to improve the DCI detection reliability. Multi-TRP URLLC schemes were introduced for PDSCH in NR Rel-16, while PDCCH robustness achieved via multi-TRP URLLC is expected to be addressed in NR Rel-17.
In addition, it was agreed in 3GPP RAN1 to support multi-DCI/multi-TRP transmission for enhanced mobile broadband (eMBB).
In addition, it was also agreed in 3GPP RAN1 to support single-DCI/multi-TRP transmission.
As briefly mentioned above, reliability can be improved by transmitting multiple copies of the same data block, with each associated with a different TRP or a different TCI state. Repetition in DL is described in 3GPP TS 38.214 (v16.0.0) section 5.1.2, the relevant parts of which are repeated below.
*** Begin excerpt from 3GPP TS 38.214 *** When receiving PDSCH scheduled by DCI format 1_1 or 1_2 in PDCCH with CRC scrambled by C-RNTI, MCS-C-RNTI, or CS-RNTI with NDI=1, if the UE is configured with pdsch-AggregationFactor in pdsch-config, the same symbol allocation is applied across the pdsch-AggregationFactor consecutive slots. When receiving PDSCH scheduled by DCI format 1_1 or 1_2 in PDCCH with CRC scrambled by CS-RNTI with NDI=0, or PDSCH scheduled without corresponding PDCCH transmission using sps-Config and activated by DCI format 1_1 or 1_2, the same symbol allocation is applied across the pdsch-AggregationFactor, in sps-Config if configured or in pdsch-config otherwise, consecutive slots. The UE may expect that the TB is repeated within each symbol allocation among each of the pdsch-AggregationFactor consecutive slots and the PDSCH is limited to a single transmission layer. For PDSCH scheduled by DCI format 1_1 or 1_2 in PDCCH with CRC scrambled by CS-RNTI with NDI=0, or PDSCH scheduled without corresponding PDCCH transmission using sps-Config and activated by DCI format 1_1 or 1_2, the UE is not expected to be configured with the time duration for the reception of pdsch-AggregationFactor repetitions, in sps-Config if configured or in pdsch-config otherwise, larger than the time duration derived by the periodicity P obtained from the corresponding sps-Config. The redundancy version to be applied on the nth transmission occasion of the TB, where n = 0,1, ...pdsch-AggregationFactor -1, is determined according to table 5.1.2.1-2 and “rvid indicated by the DCI scheduling the PDSCH” in table 5.1.2.1-2 is assumed to be 0 for PDSCH scheduled without corresponding PDCCH transmission using sps-Config and activated by DCI format 1_1 or 1_2.
*** End excerpt from 3GPP TS 38.214 *** Likewise, repetition in UL is described in 3GPP TS 38.214 (v16.0.0) section 6.1.2, the relevant parts of which are repeated below.
*** Begin excerpt from 3GPP TS 38.214 *** For PUSCH repetition Type A, when transmitting PUSCH scheduled by DCI format 0_1 or 0_2 in PDCCH with CRC scrambled with C-RNTI, MCS-C-RNTI, or CS-RNTI with NDI=1, the number of repetitions K is determined as
*** End excerpt from 3GPP TS 38.214 *** An NR slot can include 14 OFDM symbols for normal cyclic prefix and 12 symbols for extended cyclic prefix. Like in LTE, an NR resource element (RE) consists of one subcarrier in one slot, and a resource block (RB) consists of a group of 12 contiguous OFDM subcarriers for a duration of a slot (e.g., 14 symbols). Also, like LTE, NR supports slot-based scheduling but also includes a Type-B scheduling, known as “mini-slots.” These are shorter than slots, typically ranging from one symbol up to one less than the number of symbols in a slot (e.g., 13 or 11), and can start at any symbol of a slot. Mini-slots can be used if the transmission duration of a slot is too long and/or the occurrence of the next slot start (slot alignment) is too late.
Multi-antenna technology can be used to improve various aspects of a communication system (such as 5G/NR networks), including system capacity (e.g., more users per unit bandwidth per unit area), coverage (e.g., larger area for given bandwidth and number of users), and increased per-user data rate (e.g., in a given bandwidth and area). Directional antennas can also ensure better wireless links as a mobile or fixed device experiences a time-varying channel.
The availability of multiple antennas at the transmitter and/or the receiver can be utilized in different ways to achieve different goals. For example, multiple antennas can provide diversity gain against radio channel fading. A multi-antenna transmitter can achieve diversity even without any knowledge of the channels between the transmitter and the receiver, so long as there is low mutual correlation between the channels of the different transmit antennas.
In other configurations, multiple antennas at the transmitter and/or the receiver can be used to shape or “form” the overall antenna beam (e.g., transmit and/or receive beam, respectively) in a certain way, with the general goal being to improve the received signal-to-interference-plus-noise ratio (SINR) and, ultimately, system capacity and/or coverage. This can be done, for example, by maximizing the overall antenna gain in the direction of the target receiver or transmitter or by suppressing specific dominant interfering signals.
In relatively good channel conditions, the capacity of the channel becomes saturated such that further improving the SINR provides limited increases in capacity. In such cases, using multiple antennas at both the transmitter and the receiver can be used to create multiple parallel communication “channels” over the radio interface. This can facilitate a highly efficient utilization of both the available transmit power and the available bandwidth resulting in, e.g., very high data rates within a limited bandwidth without a disproportionate degradation in coverage. These techniques are commonly referred to as “spatial multiplexing” or multiple-input, multiple-output (MIMO) antenna processing.
5G networks are expected to operate in millimeter-wave (mmW) bands, such as 6 GHZ and above. Radio signals in these bands suffer from high oxygen absorption, high penetration loss, and a variety of blockage problems. On the other hand, with wavelengths less than a centimeter, it is possible to pack a large number of antenna elements into a single antenna array with a compact formfactor. Such arrays can address many of the problems associated with mmW bands. Consequently, directional transmission and reception via antenna arrays expected to be used by both UE and gNB (or TRP) in 5G. Depending on their respective radio architectures, however, such devices may be limited to transmitting/receiving in a single (or a small number) of directions simultaneously.
Configuration (B) is similar to (A) except that the different copies are transmitted in consecutive mini-slots in a slot. This can reduce latency compared to (A). Configuration (C) is an exemplary frequency-based PDSCH repetition in which different copies of a TB are transmitted in different frequency regions using different TCI states 0-2 but in the same symbol and with a single spatial layer. Configuration (D) is an exemplary spatial-based PDSCH repetition in which two different copies are transmitted on different spatial layers (e.g., with MIMO) using different TCI states 0-1.
NR supports two types of pre-configured UL resources, both of which are similar to existing LTE semi-persistent scheduling (SPS) with some enhancements such as support for transport block (TB) repetitions. In type 1, UL data transmission with configured grant is based only on RRC configuration without any L1 signaling. Type 2 is similar to the LTE SPS feature, where some parameters are preconfigured via RRC and some physical layer parameters are configured via MAC scheduling. L1 signaling is used for activation/deactivation of a type-2 grant. For example, a NR gNB explicitly activates the configured resources on PDCCH and the UE confirms reception of the activation/deactivation grant using a MAC control element.
As stated in the 3GPP TS 38.214 excerpts above, the same resource configuration is used for all K repetitions of a transport block (TB) of data, where K also includes the initial transmission. Possible values of K are {1, 2, 4, 8}. The parameters repK and repK-RV in
For both Type 1 and Type 2 PUSCH transmissions with a configured grant, when the UE is configured with repK > 1, the UE shall repeat the TB across the repK consecutive slots applying the same symbol allocation in each slot. If the UE determines that the slot configuration (as defined in 3GPP TS 38.213 section 11.1) indicates symbols allocated for PUSCH as being DL symbols instead, the transmission on that slot is omitted for multi-slot PUSCH transmission.
For both types, UL periodicity is configured via the periodicity field in
For Type 1 configured grants, time resources are configured via RRC signalling:
For Type2 configured grants, the periodicity is configured by RRC in the same way as for Type1, but the slot offset is dynamically indicated by the slot in which the UE receives the DCI that activates the Type2 configured grant. In contrast to Type1, the time domain allocation of PUSCH is indicated dynamically by DCI via the time domain resource assignment field (i.e., slot/length indicator value, SLIV) in the same way as for scheduled (non-CG) PUSCH.
After an UL grant is configured for a CG type 1, the MAC entity shall consider that the Nth sequential UL grant occurs in the symbol that satisfies the following equation (1): [(SFN × numberOfSlotsPerFrame × numberOfSymbolsPerSlot) + (slot number in the frame × numberOfSymbolsPerSlot) + symbol number in the slot] = (timeDomainOffset × numberOfSymbolsPerSlot + S + N × periodicity) modulo (1024 × numberOfSlotsPerFrame × numberOfSymbolsPerSlot), where S is the starting symbol specified by timeDomainAllocation.
Similarly, after an UL grant is configured for a CG type 2, the MAC entity shall consider that the Nth sequential UL grant occurs in the symbol that satisfies the following equation (2): [(SFN × numberOfSlotsPerFrame × numberOfSymbolsPerSlot) + (slot number in the frame × numberOfSymbolsPerSlot) + symbol number in the slot] = [SFNstarttime × numberOfSlotsPerFrame × numberOfSymbolsPerSlot + slotstarttime × numberOfSymbolsPerSlot + symbolstarttime + N × periodicity] modulo (1024 × numberOfSlotsPerFrame × numberOfSymbolsPerSlot), where SFNstarttime, slotstarttime, and symbolstarttime are the SFN, slot, and symbol, respectively, of the first transmission of PUSCH where the configured UL grant was (re-)initialised.
For example, assuming 30-kHz subcarrier spacing, to configure UL resources on consecutive slots, a UE must be configured with one of the following:
A configuredGrantTimer (CGT) is used to prevent an UL CG from overriding and/or pre-empting a TB scheduled with a dynamic grant (i.e., new transmission or retransmission), or an initial TB with another UL CG (i.e., new transmission). However, there is no explicit HARQ ACK/NACK in Rel-15. Rather, the gNB implicitly indicates an ACK by providing an UL grant for a new transmission.
Expiration of the CGT indicates an ACK for a HARQ process associated with the UL CG. The CGT is (re)started for an associated HARQ process upon PUSCH transmission based on a dynamic grant (i.e., new transmission or retransmission) or a configured grant (i.e., new transmission). The CGT is stopped when the UE has received a PDCCH indicating configured grant Type 2 activation, or upon an implicit ACK for the associated HARQ process (i.e., a grant for a new transmission).
In NR Rel-15, only an initial transmission of a TB is allowed to use either type of an UL CG. In other words, any HARQ retransmissions of a TB must rely on dynamic UL grant, which is indicated via PDCCH addressed to CS-RNTI. As briefly mentioned above, autonomous uplink (AUL) is being developed for NR Rel-16. AUL is intended to support autonomous HARQ retransmission using a configured grant. In this arrangement, a new UE timer (referred to as “CG retransmission timer” or CGRT for short) is used to protect the HARQ procedure so that the retransmission can use the same HARQ process for both transmission and retransmission of a transport block (TB) of UL data. CGRT is configured by the parameter cg-RetransmissionTimer shown in
This functionality helps the UE to avoid a HARQ process being stalled in case a gNB has missed the HARQ transmission initiated by UE. However, an observed issue is that a UE may just repetitively initiate autonomous HARQ retransmissions for a HARQ process for a long duration, but the gNB may not successfully receive the transmissions, e.g., due to bad radio channel quality or repetitive listen-before-talk (LBT) failures in case of a shared channel. This is undesirable since the data in the TB may no longer be useful and further retransmission attempts would unnecessarily congest the channel and affect the latency of other packets in the UL buffer.
The UE may eventually trigger RLC-layer retransmission for an RLC PDU that is undergoing HARQ retransmissions. However, the retransmitted RLC PDU would occupy a different HARQ process, such that the UE would then maintain two HARQ processes in transmission for the same RLC PDU and the gNB’s RLC receiver may receive duplicate RLC PDUs. This may create problems with wraparound of RLC sequence number. In addition, the second received RLC PDU may be treated as new data and passed to upper layers rather than being dropped as a duplicate.
Therefore, it is necessary to limit UE-triggered AUL retransmissions for a HARQ process. To address this issue, the existing CGT is configured to indicate the maximum amount of time for the UE to complete transmission for a HARQ process. When the CGT expires, the UE should flush the HARQ buffer for this HARQ process and transmit new data associated with it. If both CGT and CGRT are configured for a HARQ process, both timers can be operated in parallel. In this way, the UE can perform HARQ retransmission using CG resources for a HARQ process while CGT is running for the process. The value used for CGT should be longer than the value used for CGRT. An example of the above-described procedure is illustrated in
A UE can be provided with multiple active UL CGs for the UE’s active bandwidth part (BWP) in the UE’s serving cell. The availability of multiple CGs can, for example, enhance reliability and reduce latency for critical services. In addition, for NR in unlicensed spectrum (e.g., NR-U), multiple CGs can allow a UE to switch to slot-based transmissions after initiating the COT (channel occupancy time) to minimize DMRS and UCI overhead.
There can be one or more HARQ processes in the HARQ process pool assigned to each CG configuration. There is also a separate CGT timer and CGRT setting associated with each CG configuration. HARQ processes can also be shared between CG configurations, which can increase flexibility and avoid depletion of limited HARQ process space for the UE.
A logical channel (LCH) can be mapped to multiple CG configurations, such that the UE can transmit data of the LCH using multiple active CG resources at the same time. If a TB was transmitted using a CG resource, the TB can be retransmitted using the CG resource (among the set of CG resources mapped to the LCH) that comes earliest in the time, which helps to reduce the latency. However, the CG resource selected for retransmission should be the same size as the CG resource used for the initial transmission to avoid the need for rate-matching. In addition, the UE shall use the same HARQ process for transmission and retransmission of a TB.
The CGT for a HARQ process shall be only started when the TB using this HARQ process is initially transmitted. The value of the CGT is set according to the configuration of the CG resource used for the initial transmission. In parallel, the CGRT shall be (re)started for every transmission/retransmission attempt. For example, if an initial TB transmission uses a resource in CG configuration 1, the CGRT is started using the timer value included in CG configuration 1. If the TB retransmission is performed with the resource in CG configuration 2, the CGRT need to be restarted using the timer value included in CG configuration 2.
The HARQ process number field in an UL DCI (e.g., formats 0_0 and 0_1) scrambled by CS-RNTI is used to indicate which CG configuration is to be activated/deactivated/reactivated and which CG configurations are to be released. In the DCI, NDI in the received HARQ information is 0. Upon reception of an activation/deactivation/reactivation command, the UE sends the gNB a confirmation MAC CE including a bitmap in which each bit position corresponds to a particular one of the CG configurations, e.g., the bit position corresponds to the CG index.
In view of the above, there are several problems, issues, and/or difficulties with the use of UL CGs with multiple TRPs. For example, currently an UL CG is assumed for each individual TRP. The UE behavior when configured by multi TRPs is not clear, e.g., whether and/or how to perform cross TRP transmission. Furthermore, a UE does not have flexibility to modify and/or adjust a multi-TRP configuration. For example, a UE configured to transmit to TRP1 and TRP2 cannot decide to transmit only to TRP2. Additionally, the mapping of multiple TB repetitions to specific TRPs is not specified. As an example, if K repetitions are required for URLLC, which of the K repetitions are transmitted by available TRPs is undefined. Moreover, autonomous re-transmission across multiple TRPs is not defined.
Accordingly, embodiments of the present disclosure provide novel, flexible, and efficient techniques for a UE to select among a plurality of multi-TRP configurations available for transmission in relation to an UL CG. For example, the UE can select a particular multi-TRP configuration based on various factors such as UL data for transmission at the UE (e.g., amount, arrival rate, type of service, QoS requirements, etc.), UE energy consumption, UL radio channel conditions, etc. The UE can then transmit (or retransmit) UL data to the multiple TRPs based on the selected configuration. By selecting and utilizing multi-TRP configuration in this manner, the UE can reduce energy consumption and/or improve data transmission reliability and/or latency.
The following description of exemplary embodiments is given in the context of NR, including licensed and unlicensed operation, such as NR-U. Even so, NR-U is only exemplary, and embodiments are equally applicable to other licensed (e.g., LTE) and unlicensed (e.g., LTE LAA/eLAA/feLAA /MulteFire) operation. In general, embodiments are applicable to any UE-triggered transmission that is made without receiving dynamically assigned resources from a serving network node (e.g., gNB).
According to a first group of embodiments, a UE is configured with one or more UL CG configurations that include, contain, and/or are associated with a set of CG resources across multiple TRPs. Each of these can be referred to as a “multi-TRP configuration” and can include the number of transmissions to each TRP, TCI state of each TRP, BWP/SCS of each TRP, etc. For example, the CG resources comprising an UL CG configuration may be associated with different TRPs, e.g., TRPi, where i=1...N. In addition, for each time-domain transmission occasion associated with an UL CG, there may be multiple CG resources in the frequency domain (e.g., that overlap in time). According to various embodiments described below, the UE can use various techniques to determine which CG resource shall be chosen for each transmission occasion.
In some embodiments, the UE can select the CG resource for UL transmission that is associated with the highest-quality DL radio channel from a TRP to the UE. The DL radio channel quality may be measured by the UE in terms of various metrics such as reference signal received power (RSRP), reference signal received quality (RSRQ), received signal strength (RSSI), signal-to-interference-and-noise ratio (SINR), signal-to-interference ratio (SIR), channel occupancy, listen-before-talk (LBT) failures, clear channel assessment (CCA) failures (e.g., count or success/failure ratio), etc.
In other embodiments, the UE can select the CG resource for UL transmission that is associated with the highest-quality UL radio channel from the UE to a TRP. The UL radio connection quality may be measured by the UE in terms of various metrics, including any of the following:
In other embodiments, the UE can select the CG resource for UL transmission that provides the highest UL bit rate and/or the shortest PUSCH transmission duration (e.g., highest capacity modulation and coding scheme, MCS). In other embodiments, the UE can select the CG resource for UL transmission that provides highest transmission reliability (e.g., most reliable MCS).
In some embodiments, the network (e.g., gNB) can configure each UE to use one or more of the above selection criteria via dedicated RRC signaling, MAC CE, or DCI. In other embodiments, the network can broadcast system information (SI) that indicates which of the selection criteria should be used by UEs in the cell.
In some embodiments, the exemplary ASN.1 data structure for a ConfiguredGrantConfig IE shown in
The enhancements shown in
According to a second group of embodiments, a UE is configured with one or more UL CG configurations that include, contain, and/or are associated with a set of CG resources across multiple TRPs. Each of these can be referred to as a “multi-TRP configuration.” For example, the CG resources comprising an UL CG configuration may be associated with different TRPs, e.g., TRPi, where i=1...N. In addition, for each time-domain transmission occasion associated with an UL CG, there may be multiple CG resources in the frequency domain (e.g., that overlap in time). According to various embodiments described below, the UE can use various techniques to select CG resources to be used for retransmissions of TBs, e.g., towards another TRP than for the initial transmission.
In some embodiments, if autonomous retransmission is triggered upon expiry of a timer and the UE has not received explicit or implicit positive HARQ feedback from the gNB, the UE can select the same UL CG configuration for retransmission as used for initial transmission (e.g., transmitting to the same TRP) or a different UL CG configuration. In some embodiments, the network can configure (e.g., via RRC signaling) whether the UE should use the same or different UL CG configuration in this scenario.
In some embodiments, an UL CG configuration may include an indication (e.g., in an IE field) of whether TB repetition is allowed and/or the number of repetitions allowed. For example, the UE can base its selection of UL CG configurations on this indication and the degree of reliability needed for the particular TB.
In some embodiments, a UE may perform multiple retransmissions or repetitions of a TB using different frequency resources that overlap in time (e.g., at the same transmission occasion). By performing multiple retransmissions simultaneously, the latency for receiving HARQ A/N from the gNB can be reduced as compared to transmitting them sequentially (e.g., with no intermediate responses).
In some embodiments, the UE can apply any of the same criteria discussed above (e.g., with respect to the first group) for selecting a CG resource to be used for a retransmission or repetition of a TB. For example, the UE is configured with first and second UL CG configurations and selects a CG resource of the first UL CG configuration for initial transmission according to the above-described criteria. Subsequently, the UE can select a different CG resource in the second UL CG configuration for retransmission or repetition of the same TB.
In some embodiments, a UE is configured with a plurality of UL CG configurations, each of which includes a set of periodic CG resources associated with one of a plurality of TRPs. Using the above example of two UL CG configurations and two TRPs, a first UL CG configurations can include periodic CG resources associated with a first TRP and a second UL CG configuration can include periodic CG resources associated with a second TRP. As such, the UE can select a CG resource of the first UL CG configuration for initial transmission towards the first TRP, and select a different CG resource in the second UL CG configuration for retransmission or repetition of the same TB towards the second TRP.
In some embodiments, multiple PUSCH repetitions can be transmitted towards multiple TRPs at the same time or at different (i.e., non-overlapping) times. The PUSCH can be associated with a dynamic UL grant via DCI, or with an UL CG. As such, these transmissions (repetitions) over multiple-TRPs can belong to the same HARQ process or to different HARQ processes or sub-HARQ processes. Note for a single HARQ process, repetitions associated with different TRPs can be considered as separate sub-HARQ processes, and the gNB combines transmissions for these sub-HARQ processes to derive a single transmission for the HARQ process.
In some embodiments, for CGs not associated with a DCI, PUSCH repetitions toward multiple TRPs can be associated with a single CG or different CGs (e.g., each TRP associated with a separate CG). In some embodiments, PUSCH repetitions toward multiple TRPs can be aligned or non-aligned in time. To make transmissions or repetitions aligned, the gNB or UE can trigger processes in an aperiodic or periodic manner to make a secondary TRP aligned or synchronized with respect to a primary TRP.
In some embodiments, UL CG transmissions toward multiple TRPs can be activated with a DCI from a single TRP. This DCI can provide necessary information for CG allocation over multiple TRPs associated with a single CG or different CGs (e.g., each TRP associated with a separate CG). In other embodiments, UL CG transmissions toward multiple TRPs can be activated with multiple DCIs, with each DCI associated with a different UL CG and each UL CG associated with a different TRP.
As an illustrative example, a UE is configured with two different multi-TRP UL CG configurations (e.g., for TRPs 1 and 2), both of which include K=4 TB repetitions. Configuration 1 (C1) includes four TB repetitions to TRP1 and zero repetitions to TRP2, while C2 includes two repetitions to TRP1 and two repetitions to TRP2. Data for UL transmission may arrive at the UE (e.g., provided by a user or an application) at different times relative to UL transmission occasions available to the UE.
In the context of the above example, if only one repetition is configured (i.e., K=1), the UE can select the UL CG configuration that includes CG resources for the TRP (e.g., 1 or 2) having the better radio channel quality towards the UE. This can be determined based on any of the metrics discussed above.
In some embodiments, selection and configuration of which TRPs to use to may depend on the respective loads of the TRPs and/or interference created by transmission towards the respective TRPs. In such case, the selection of TRPs may be based on the geographical distribution of UEs in the cell.
Although the above description focused on UL transmission using UL CGs, the same principles can be applied to DL transmissions based on semi-persistent scheduling (SPS). Furthermore, the same principles can be applied to dynamic UL grants that include repetitions.
Carrier aggregation (CA) was introduced in LTE Rel-10 to facilitate support for bandwidths larger than 20 MHz while remaining backward compatible with LTE Rel-8. In CA, a wideband LTE carrier (e.g., wider than 20 MHz) appears as multiple carriers (also referred to as “component carriers” or “CCs”) to a UE. Each CC can also be referred to as a “cell”, and the UE’s full set of CCs can be considered a “cell group”. In CA operation a UE is always assigned a primary cell (PCell, as a main serving cell) and may optionally be assigned one or more secondary cells (SCells). CA is also used in 5G/NR.
Although the above description focused on UL transmission to multiple TRPs, the same principles can be applied to selection between configurations that are associated with UL transmissions to multiple cells or on multiple CCs arranged in CA. In other words, rather than selecting a multi-TRP configuration according to various criteria, the UE can select a multi-cell or multi-carrier configuration according to the same or different criteria.
In some embodiments, different UEs may have different capabilities for selecting among configured UL CGs according to the above principles. UEs may signal these capabilities to the network, which can then take them into consideration when providing UL CGs to such UEs.
The embodiments described above are further illustrated with reference to
More specifically,
The exemplary method can include operations of block 1110, where the UE can receive, from the wireless network, configurations for a plurality of configured grants of resources for UL transmission (UL CGs). At least one of the UL CG configurations can include resources for transmission to a plurality of TRPs. The exemplary method can also include operations of block 1150, where the UE can select one or more of the UL CG configurations for transmission of data available at the UE based on characteristics of the data and/or of radio channels between the UE and the respective TRPs. The exemplary method can also include operations of block 1160, where the UE can transmit the data to one or more of the plurality of TRPs on resources of the selected one or more UL CG configurations.
In some embodiments, the characteristics associated with the radio channel include radio channel quality. In such embodiments, the exemplary method can also include the operations of block 1120 or block 1130. In block 1120, the UE can determine respective radio channel qualities between the UE and the respective TRPs according to one or more of the following metrics: reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), signal-to-interference ratio (SIR), received signal strength (RSSI), retransmission ratio, packet loss ratio, channel occupancy, listen-before-talk (LBT) failures, and clear channel assessment (CCA) failures. Alternately, in block 1130, the UE can receive indications of the respective radio channel qualities from the wireless network. The received indications can be for any of the metrics used in block 1120, or different metrics.
In some embodiments, the characteristics associated with the radio channel can include latency characteristics. In some embodiments, the characteristics associated with the data can include amount, arrival rate, arrival time, type of service, latency requirements, and reliability requirements.
In some embodiments, each UL CG configuration identifies a plurality of transmission opportunities. In such embodiments, the selecting operations of block 1150 can include the operations of sub-block 1151, where the UE can select an UL CG configuration based on arrival time of the data relative to the transmission opportunities identified by the respective UL CG configurations.
In some embodiments, the resources of the UL CGs can be associated with respective modulation and coding schemes (MCS). In such embodiments, the selecting operations of block 1150 can include the operations of sub-block 1152, where the UE can select an UL CG configuration that includes resources associated with one of the following: highest capacity MCS, or most reliable MCS.
In some embodiments, the data comprises a transport block (TB). In such embodiments, each UL CG configuration identifies a particular number of TRPs and respective numbers of repetitions of the TB to be transmitted to the respective ones of the particular number of TRPs.
In some of these embodiments, the one or more repetitions are a single repetition, i.e., a single repetition is transmitted in block 1160. In such embodiments, the selecting operations of block 1150 can include the operations of sub-block 1153, where the UE can select an UL CG configuration that includes resources associated with the TRP having the best radio channel quality towards the UE. In such embodiments, the transmitting operations of block 1160 can include the operations of sub-block 1161, where the UE can transmit the single repetition of the TB to the TRP having the best radio channel quality towards the UE.
In other of these embodiments, the one or more repetitions include a plurality of repetitions. In such embodiments, first and second UL CG configurations are selected (e.g., in block 1150) and the transmitting operations of block 1160 can include the operations of sub-blocks 1162-1163. In sub-block 1162, the UE can transmit a first portion of the plurality of repetitions on resources of the first UL CG configuration. In sub-block 1163, the UE can transmit a second portion of the plurality of repetitions on resources of the second UL CG configuration.
In other of these embodiments, the plurality of UL CG configurations can include a first UL CG configuration that identifies a first TRP to which all repetitions of the TB are transmitted, and a second UL CG configuration that identifies the first TRP and a first number of repetitions and a second TRP and a second number of repetitions. In such embodiments, the transmitting operations of block 1160 include the operations of sub-blocks 1164 or 1165. In sub-block 1164, when the first UL CG configuration is selected (e.g., in block 1150), the UE transmits respective repetitions of the TB to the first TRP in respective transmission opportunities. In sub-block 1165, when the second UL CG configuration is selected (e.g., in block 1150), the UE transmits at least one of the first number of repetitions to the first TRP concurrently with at least one of the second number of repetitions to the second TRP in one or more of the transmission opportunities.
As a more detailed example of such embodiments, one of the following first conditions applies for each of the one or more transmission opportunities: a single repetition of the first number is transmitted to the first TRP; or a plurality of the first number are transmitted to the first TRP in a respective plurality of frequency regions. In addition, one of the following second conditions applies for each of the one or more transmission opportunities: a single repetition of the second number is transmitted to the second TRP; or a plurality of the second number are transmitted to the second TRP in the respective plurality of frequency regions.
In some embodiments, the data comprises a transport block (TB) associated with a HARQ process. In such embodiments, first and second UL CG configurations are selected and the transmitting operations of block 1160 can include the operations of sub-blocks 1166-1167. In sub-block 1166, the UE can transmit an initial transmission of the TB on resources of the first UL CG configuration. In sub-block 1167, the UE can transmit at least one retransmission of the TB on resources of the second UL CG configuration.
In some of these embodiments, the resources of the first UL CG configuration are associated with a first TRP and the resources of the second UL CG configuration are associated with a second TRP. In this manner, the initial transmission (e.g., in sub-block 1166) and the at least one retransmission (e.g., in sub-block 1167) will be transmitted to different TRPs.
In some of these embodiments, the exemplary method can also include the operations of block 1140, where the UE can receive, from the wireless network, an indication that different UL CG configurations can be selected for transmission and retransmission in a single HARQ process. In such embodiments, the selection of the second UL CG configuration (e.g., in block 1150) can be based on this indication.
In addition,
The exemplary method can include operations of block 1210, where the network node can transmit, to a UE, configurations for a plurality of configured grants of resources for UL transmission (UL CGs). At least one of the UL CG configurations can include resources for UE transmission to a plurality of TRPs. The exemplary method can also include operations of block 1250, where the network node can receive UL data, from the UE via one or more of the plurality of TRPs, on resources of the one or more of the UL CG configurations that were selected by the UE, e.g., in any of the ways described above.
In some embodiments, the exemplary method can also include the operations of blocks 1220-1230. In block 1220, the network node can determine respective radio channel qualities between the UE and the respective TRPs according to one or more of the following metrics: reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), signal-to-interference ratio (SIR), received signal strength (RSSI), retransmission ratio, packet loss ratio, channel occupancy, listen-before-talk (LBT) failures, and clear channel assessment (CCA) failures. In block 1230, the network node can send indications of the determined radio channel qualities to the UE.
In some embodiments, each UL CG configuration identifies a plurality of transmission opportunities. In such embodiments, the selected UL CG (e.g., by the UE in relation to the data received in block 1250) is related to arrival time of the data at the UE relative to the transmission opportunities identified by the respective UL CG configurations.
In some embodiments, the resources of the UL CGs can be associated with respective MCS. In such embodiments, the selected UL CG (e.g., by the UE in relation to the data received in block 1250) includes resources associated with one of the following: highest capacity MCS, or most reliable MCS.
In some embodiments, the data comprises a transport block (TB). In such embodiments, each UL CG configuration identifies a particular number of TRPs and respective numbers of repetitions of the TB to be transmitted by the UE to respective ones of the particular number of TRPs.
In some of these embodiments, the one or more repetitions are a single repetition. In such embodiments, the receiving operations of block 1250 can include the operations of sub-block 1251, where the network node can receive the single repetition of the TB via the TRP having the best radio channel quality towards the UE (e.g., as selected by the UE).
In other of these embodiments, the one or more repetitions include a plurality of repetitions. In such embodiments, the receiving operations of block 1250 can include the operations of sub-blocks 1252-1253, where the network node can receive a first portion of the plurality of repetitions on resources of a first UL CG configuration and receive a second portion of the plurality of repetitions on resources of a second UL CG configuration.
In other of these embodiments, the plurality of UL CG configurations can include a first UL CG configuration that identifies a first TRP to which all repetitions are transmitted, and a second UL CG configuration that identifies the first TRP and a first number of repetitions and a second TRP and a second number of repetitions. In such embodiments, the receiving operations of block 1250 can include the operations of sub-blocks 1254 or 1255. In sub-block 1254, when the first UL CG configuration is selected, the network node can receive respective repetitions of the TB via the first TRP in respective transmission opportunities. In sub-block 1255, when the second UL CG configuration is selected, the network node can receive at least one of the first number of repetitions via the first TRP concurrently with at least one of the second number of repetitions via the second TRP in one or more of the transmission opportunities.
As a more detailed example of such embodiments, one of the following first conditions applies for each of the one or more transmission opportunities: a single repetition of the first number is received via the first TRP; or a plurality of the first number are received via the first TRP in a respective plurality of frequency regions. In addition, one of the following second conditions applies for each of the one or more transmission opportunities: a single repetition of the second number is received via the second TRP; or a plurality of the second number are received via the second TRP in the respective plurality of frequency regions.
In some embodiments, the data comprises a transport block (TB) associated with a hybrid ARQ (HARQ) process. In such embodiments, the receiving operations of block 1250 can include one or more of the operations of sub-blocks 1256-1257. In sub-block 1256, the network node can receive an initial transmission of the TB on resources of first UL CG configuration. In sub-block 1257, the network node can receive at least one retransmission of the TB on resources of the second UL CG configuration. For example, the initial transmission may or may not be received (e.g., due to prevailing channel conditions), but any reception will be on resources of the first UL CG configuration. Similarly, the retransmission(s) may or may not be received (e.g., due to prevailing channel conditions), but any reception will be on resources of the second UL CG configuration.
In some of these embodiments, the resources of the first UL CG configuration are associated with a first TRP and the resources of the second UL CG configuration are associated with a second TRP. In this manner, the initial transmission and the at least one retransmission can be received via different TRPs (e.g., in sub-blocks 1256-1257).
In some embodiments, the exemplary method can also include the operations of block 1240, where the network node can transmit, to the UE, an indication that different UL CG configurations can be selected for transmission and retransmission in a single HARQ process. In such embodiments, the reception on resources of the second UL CG configuration in sub-block 1257 can be based on this indication.
Although various embodiments are described herein above in terms of methods, apparatus, devices, computer-readable medium and receivers, the person of ordinary skill will readily comprehend that such methods can be embodied by various combinations of hardware and software in various systems, communication devices, computing devices, control devices, apparatuses, non-transitory computer-readable media, etc.
Exemplary device 1300 can comprise a processor 1310 that can be operably connected to a program memory 1320 and/or a data memory 1330 via a bus 1370 that can comprise parallel address and data buses, serial ports, or other methods and/or structures known to those of ordinary skill in the art. Program memory 1320 can store software code, programs, and/or instructions (collectively shown as computer program product 1321 in
As another example, processor 1310 can execute program code stored in program memory 1320 that corresponds to MAC, RLC, PDCP, and RRC layer protocols standardized by 3GPP (e.g., for NR and/or LTE). As a further example, processor 1310 can execute program code stored in program memory 1320 that, together with radio transceiver 1340, implements corresponding PHY layer protocols, such as Orthogonal Frequency Division Multiplexing (OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), and Single-Carrier Frequency Division Multiple Access (SC-FDMA).
Program memory 1320 can also comprises software code executed by processor 1310 to control the functions of device 1300, including configuring and controlling various components such as radio transceiver 1340, user interface 1350, and/or host interface 1360. Program memory 1320 can also comprise one or more application programs and/or modules comprising computer-executable instructions embodying any of the exemplary methods and/or procedures described herein. Such software code can be specified or written using any known or future developed programming language, such as e.g., Java, C++, C, Objective C, HTML, XHTML, machine code, and Assembler, as long as the desired functionality, e.g., as defined by the implemented method steps, is preserved. In addition, or as an alternative, program memory 1320 can comprise an external storage arrangement (not shown) remote from device 1300, from which the instructions can be downloaded into program memory 1320 located within or removably coupled to device 1300, so as to enable execution of such instructions.
Data memory 1330 can comprise memory area for processor 1310 to store variables used in protocols, configuration, control, and other functions of device 1300, including operations corresponding to, or comprising, any of the exemplary methods and/or procedures described herein. Moreover, program memory 1320 and/or data memory 1330 can comprise non-volatile memory (e.g., flash memory), volatile memory (e.g., static or dynamic RAM), or a combination thereof. Furthermore, data memory 1330 can comprise a memory slot by which removable memory cards in one or more formats (e.g., SD Card, Memory Stick, Compact Flash, etc.) can be inserted and removed. Persons of ordinary skill in the art will recognize that processor 1310 can comprise multiple individual processors (including, e.g., multi-core processors), each of which implements a portion of the functionality described above. In such cases, multiple individual processors can be commonly connected to program memory 1320 and data memory 1330 or individually connected to multiple individual program memories and or data memories. More generally, persons of ordinary skill in the art will recognize that various protocols and other functions of device 1300 can be implemented in many different computer arrangements comprising different combinations of hardware and software including, but not limited to, application processors, signal processors, general-purpose processors, multi-core processors, ASICs, fixed and/or programmable digital circuitry, analog baseband circuitry, radio-frequency circuitry, software, firmware, and middleware.
A radio transceiver 1340 can comprise radio-frequency transmitter and/or receiver circuitry that facilitates the device 1300 to communicate with other equipment supporting like wireless communication standards and/or protocols. In some exemplary embodiments, the radio transceiver 1340 includes a transmitter and a receiver that enable device 1300 to communicate with various 5G/NR networks according to various protocols and/or methods proposed for standardization by 3GPP and/or other standards bodies. For example, such functionality can operate cooperatively with processor 1310 to implement a PHY layer based on OFDM, OFDMA, and/or SC-FDMA technologies, such as described herein with respect to other figures.
In some exemplary embodiments, radio transceiver 1340 includes an LTE transmitter and receiver that can facilitate device 1300 to communicate with various LTE, LTE-Advanced (LTE-A), and/or NR networks according to standards promulgated by 3GPP. In some exemplary embodiments, radio transceiver 1340 includes circuitry, firmware, etc. necessary for the device 1300 to communicate with various 5G/NR, LTE, LTE-A, UMTS, and/or GSM/EDGE networks, also according to 3GPP standards. In some exemplary embodiments of the present disclosure, radio transceiver 1340 includes circuitry, firmware, etc. necessary for the device 1300 to communicate with various CDMA2000 networks, according to 3GPP2 standards.
In some exemplary embodiments of the present disclosure, the radio transceiver 1340 is capable of communicating using radio technologies that operate in unlicensed frequency bands, such as IEEE 802.11 WiFi that operates using frequencies in the regions of 2.4, 5.6, and/or 60 GHz. In some exemplary embodiments, radio transceiver 1340 can include circuitry, firmware, etc. necessary for the device 1300 to communicate using cellular protocols in unlicensed or shared spectrum, e.g., via NR-U, LTE LAA/eLAA/feLAA, MulteFire, etc.
In some exemplary embodiments of the present disclosure, radio transceiver 1340 can comprise a transceiver that is capable of wired communication, such as by using IEEE 802.3 Ethernet technology.
The functionality of radio transceiver 1340 specific to each of these embodiments can be coupled with and/or controlled by other circuitry in the device 1300, such as the processor 1310 executing program code stored in program memory 1320 in conjunction with, or supported by, data memory 1330.
User interface 1350 can take various forms depending on the particular embodiment of device 1300 or can be absent from device 1300 entirely. In some exemplary embodiments, user interface 1350 can comprise a microphone, a loudspeaker, slidable buttons, depressible buttons, a display, a touchscreen display, a mechanical or virtual keypad, a mechanical or virtual keyboard, and/or any other user-interface features commonly found on mobile phones. In other embodiments, the device 1300 can comprise a tablet computing device including a larger touchscreen display. In such embodiments, one or more of the mechanical features of the user interface 1350 can be replaced by comparable or functionally equivalent virtual user interface features (e.g., virtual keypad, virtual buttons, etc.) implemented using the touchscreen display, as familiar to persons of ordinary skill in the art. In other embodiments, the device 1300 can be a digital computing device, such as a laptop computer, desktop computer, workstation, etc. that comprises a mechanical keyboard that can be integrated, detached, or detachable depending on the particular exemplary embodiment. Such a digital computing device can also comprise a touch screen display. Many exemplary embodiments of the device 1300 having a touch screen display are capable of receiving user inputs, such as inputs related to exemplary methods and/or procedures described herein or otherwise known to persons of ordinary skill in the art.
In some exemplary embodiments of the present disclosure, device 1300 can comprise an orientation sensor, which can be used in various ways by features and functions of device 1300. For example, the device 1300 can use outputs of the orientation sensor to determine when a user has changed the physical orientation of the device 1300′s touch screen display. An indication signal from the orientation sensor can be available to any application program executing on the device 1300, such that an application program can change the orientation of a screen display (e.g., from portrait to landscape) automatically when the indication signal indicates an approximate 90-degree change in physical orientation of the device. In this exemplary manner, the application program can maintain the screen display in a manner that is readable by the user, regardless of the physical orientation of the device. In addition, the output of the orientation sensor can be used in conjunction with various exemplary embodiments of the present disclosure.
A control interface 1360 of the device 1300 can take various forms depending on the particular exemplary embodiment of device 1300 and of the particular interface requirements of other devices that the device 1300 is intended to communicate with and/or control. For example, the control interface 1360 can comprise an RS-232 interface, an RS-485 interface, a USB interface, an HDMI interface, a Bluetooth interface, an IEEE (“Firewire”) interface, an I2C interface, a PCMCIA interface, or the like. In some exemplary embodiments of the present disclosure, control interface 1360 can comprise an IEEE 802.3 Ethernet interface such as described above. In some exemplary embodiments of the present disclosure, the control interface 1360 can comprise analog interface circuitry including, for example, one or more digital-to-analog (D/A) and/or analog-to-digital (A/D) converters.
Persons of ordinary skill in the art can recognize the above list of features, interfaces, and radio-frequency communication standards is merely exemplary, and not limiting to the scope of the present disclosure. In other words, the device 1300 can comprise more functionality than is shown in
Program memory 1420 can store software code, programs, and/or instructions (collectively shown as computer program product 1421 in
Data memory 1430 can comprise memory area for processor 1410 to store variables used in protocols, configuration, control, and other functions of network node 1400. As such, program memory 1420 and data memory 1430 can comprise non-volatile memory (e.g., flash memory, hard disk, etc.), volatile memory (e.g., static or dynamic RAM), network-based (e.g., “cloud”) storage, or a combination thereof. Persons of ordinary skill in the art will recognize that processor 1410 can comprise multiple individual processors (not shown), each of which implements a portion of the functionality described above. In such case, multiple individual processors may be commonly connected to program memory 1420 and data memory 1430 or individually connected to multiple individual program memories and/or data memories. More generally, persons of ordinary skill in the art will recognize that various protocols and other functions of network node 1400 may be implemented in many different combinations of hardware and software including, but not limited to, application processors, signal processors, general-purpose processors, multi-core processors, ASICs, fixed digital circuitry, programmable digital circuitry, analog baseband circuitry, radio-frequency circuitry, software, firmware, and middleware.
Radio network interface 1440 can comprise transmitters, receivers, signal processors, ASICs, antennas, beamforming units, and other circuitry that enables network node 1400 to communicate with other equipment such as, in some embodiments, a plurality of compatible user equipment (UE). In some exemplary embodiments, radio network interface 1440 can comprise various protocols or protocol layers, such as the PHY, MAC, RLC, PDCP, and RRC layer protocols standardized by 3GPP for NR, NR-U, LTE, LTE-A, and/or LTE LAA/eLAA/feLAA; improvements thereto such as described herein above; or any other higher-layer protocols utilized in conjunction with radio network interface 1440. According to further exemplary embodiments, the radio network interface 1440 can comprise a PHY layer based on OFDM, OFDMA, and/or SC-FDMA technologies. In some embodiments, the functionality of such a PHY layer can be provided cooperatively by radio network interface 1440 and processor 1410, possibly in conjunction with program code or computer program product 1421 in memory 1420.
Core network interface 1450 can comprise transmitters, receivers, and other circuitry that enables network node 1400 to communicate with other equipment in a core network such as, in some embodiments, circuit-switched (CS) and/or packet-switched Core (PS) networks. In some embodiments, core network interface 1450 can comprise the S1 interface standardized by 3GPP. In some exemplary embodiments, core network interface 1450 can comprise one or more interfaces to one or more SGWs, MMEs, SGSNs, GGSNs, and other physical devices that comprise functionality found in GERAN, UTRAN, E-UTRAN, and CDMA2000 core networks that are known to persons of ordinary skill in the art. In some embodiments, these one or more interfaces may be multiplexed together on a single physical interface. In some embodiments, lower layers of core network interface 1450 can comprise one or more of asynchronous transfer mode (ATM), Internet Protocol (IP)-over-Ethernet, SDH over optical fiber, T1/E1/PDH over a copper wire, microwave radio, integrated access backhaul (IAB), or other wired or wireless transmission technologies known to those of ordinary skill in the art.
OA&M interface 1460 can comprise transmitters, receivers, and other circuitry that enables network node 1400 to communicate with external networks, computers, databases, and the like for purposes of operations, administration, and maintenance of network node 1400 or other network equipment operably connected thereto. Lower layers of OA&M interface 1460 can comprise one or more of asynchronous transfer mode (ATM), Internet Protocol (IP)-over-Ethernet, SDH over optical fiber, T1/E1/PDH over a copper wire, microwave radio, or other wired or wireless transmission technologies known to those of ordinary skill in the art. Moreover, in some embodiments, one or more of radio network interface 1440, core network interface 1450, and OA&M interface 1460 may be multiplexed together on a single physical interface, such as the examples listed above.
RAN 1530 can further communicate with core network 1540 according to various protocols and interfaces described above. For example, one or more apparatus (e.g., base stations, eNBs, gNBs, etc.) comprising RAN 1530 can communicate to core network 1540 via core network interface 1550 described above. In some exemplary embodiments, RAN 1530 and core network 1540 can be configured and/or arranged as shown in other figures discussed above. For example, eNBs comprising an E-UTRAN 1530 can communicate with an EPC core network 1540 via an S1 interface, such as illustrated in
Core network 1540 can further communicate with an external packet data network, illustrated in
For example, host computer 1560 can provide an over-the-top (OTT) packet data service to UE 1510 using facilities of core network 1540 and RAN 1530, which can be unaware of the routing of an outgoing/incoming communication to/from host computer 1560. Similarly, host computer 1560 can be unaware of routing of a transmission from the host computer to the UE, e.g., the routing of the transmission through RAN 1530. Various OTT services can be provided using the exemplary configuration shown in
The exemplary network shown in
The exemplary embodiments described herein provide flexible and efficient techniques for a UE to select among a plurality of multi-TRP configurations available for transmission in relation to an UL CG based on various factors such as UL data for transmission at the UE, UE energy consumption, UL/DL radio channel conditions, etc. By selecting and utilizing multi-TRP configuration in this manner, the UE can reduce energy consumption and/or improve data transmission reliability and/or latency. When used in NR UEs (e.g., UE 1510) and gNBs (e.g., gNBs comprising RAN 1530), exemplary embodiments described herein can provide various improvements, benefits, and/or advantages that improve the performance of UEs and OTT data services as experienced by OTT service providers and end-users. These include more reliable UL data throughout and reduced UL latency without excessive UE power consumption or other reductions in user experience.
The foregoing merely illustrates the principles of the disclosure. Various modifications and alterations to the described embodiments will be apparent to those skilled in the art in view of the teachings herein. It will thus be appreciated that those skilled in the art will be able to devise numerous systems, arrangements, and procedures that, although not explicitly shown or described herein, embody the principles of the disclosure and can be thus within the spirit and scope of the disclosure. Various exemplary embodiments can be used together with one another, as well as interchangeably therewith, as should be understood by those having ordinary skill in the art.
The term unit, as used herein, can have conventional meaning in the field of electronics, electrical devices and/or electronic devices and can include, for example, electrical and/or electronic circuitry, devices, modules, processors, memories, logic solid state and/or discrete devices, computer programs or instructions for carrying out respective tasks, procedures, computations, outputs, and/or displaying functions, and so on, as such as those that are described herein.
Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include Digital Signal Processor (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as Read Only Memory (ROM), Random Access Memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.
As described herein, device and/or apparatus can be represented by a semiconductor chip, a chipset, or a (hardware) module comprising such chip or chipset; this, however, does not exclude the possibility that a functionality of a device or apparatus, instead of being hardware implemented, be implemented as a software module such as a computer program or a computer program product comprising executable software code portions for execution or being run on a processor. Furthermore, functionality of a device or apparatus can be implemented by any combination of hardware and software. A device or apparatus can also be regarded as an assembly of multiple devices and/or apparatuses, whether functionally in cooperation with or independently of each other. Moreover, devices and apparatuses can be implemented in a distributed fashion throughout a system, so long as the functionality of the device or apparatus is preserved. Such and similar principles are considered as known to a skilled person.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
In addition, certain terms used in the present disclosure, including the specification and drawings, can be used synonymously in certain instances (e.g., “data” and “information”). It should be understood, that although these terms (and/or other terms that can be synonymous to one another) can be used synonymously herein, there can be instances when such words can be intended to not be used synonymously. Further, to the extent that the prior art knowledge has not been explicitly incorporated by reference herein above, it is explicitly incorporated herein in its entirety. All publications referenced are incorporated herein by reference in their entireties.
The techniques and apparatus described herein include, but are not limited to, the following enumerated examples:
A1. A method, for a user equipment (UE), of uplink (UL) transmission of data to a plurality of transmission reception points (TRPs) in a wireless network, the method comprising:
A2. The method of embodiment A1, wherein:
A3. The method of any of embodiments A1-A2, wherein the characteristics associated with the radio channel include latency.
A4. The method of any of embodiments A1-A3, wherein the characteristics associated with the data include amount, arrival rate, arrival time, type of service, latency requirements, and reliability requirements.
A5. The method of embodiment A4, wherein:
A6. The method of any of embodiments A1-A5, wherein:
A7. The method of any of embodiments A1-A6, wherein:
A8. The method of embodiment A7, wherein:
A9. The method of embodiment A7, wherein:
A10. The method of embodiment A7, wherein the plurality of UL CG configurations include:
A11. The method of embodiment A10, wherein:
A12. The method of embodiment A11, wherein:
A13. The method of any of embodiments A1-A6, wherein:
A14. The method of embodiment A13, further comprising receiving, from the wireless network, an indication that different UL CG configurations can be selected for transmission and retransmission in a single HARQ process, wherein selecting the second UL CG configuration is based on the indication.
A15. The method of any of embodiments A13-A14, wherein:
B1. A method, for a network node in a wireless network, of receiving uplink (UL) transmission of data via a plurality of transmission reception points (TRPs), the method comprising:
B2. The method of embodiment B1, further comprising:
B3. The method of any of embodiments B1-B2, wherein:
B4. The method of any of embodiments B1-B3, wherein:
B5. The method of any of embodiments B1-B4, wherein:
B6. The method of embodiment B5, wherein:
B7. The method of embodiment B5, wherein:
B8. The method of embodiment B5, wherein the plurality of UL CG configurations include:
B9. The method of embodiment B8, wherein receiving the data comprises:
B10. The method of embodiment B9, wherein in each of the one or more transmission opportunities, one of the following first conditions applies:
B11. The method of any of embodiments B1-B4, wherein:
B12. The method of embodiment B11, further comprising transmitting, to the UE, an indication that different UL CG configurations can be selected for transmission and retransmission in a single HARQ process.
B13. The method of any of embodiments B11-B12, wherein:
C1. A user equipment (UE) configured for uplink (UL) transmission of data to a plurality of transmission reception points (TRPs) in a wireless network, the UE comprising:
C2. A user equipment (UE) configured for uplink (UL) transmission of data to a plurality of transmission reception points (TRPs) in a wireless network, the UE being arranged to perform operations corresponding to the methods of any of embodiments A1- A15.
C3. A non-transitory, computer-readable medium storing computer-executable instructions that, when executed by processing circuitry of a user equipment (UE) configured for uplink (UL) transmission of data to a plurality of transmission reception points (TRPs) in a wireless network, configure the UE to perform operations corresponding to any of the methods of embodiments A1- A15.
C4. A computer program product comprising computer-executable instructions that, when executed by processing circuitry of a user equipment (UE) configured for uplink (UL) transmission of data to a plurality of transmission reception points (TRPs) in a wireless network, configure the UE to perform operations corresponding to any of the methods of embodiments A1-A15.
D1. A network node configured to receive uplink (UL) transmission of data via a plurality of transmission reception points (TRPs) in a wireless network, the network node comprising:
D2. A network node configured to receive uplink (UL) transmission of data via a plurality of transmission reception points (TRPs) in a wireless network, the network node being arranged to perform operations corresponding to any of the methods of embodiments B1- B13.
D3. A non-transitory, computer-readable medium storing computer-executable instructions that, when executed by processing circuitry of a network node configured to receive uplink (UL) transmission of data via a plurality of transmission reception points (TRPs) in a wireless network, configure the network node to perform operations corresponding to any of the methods of embodiments B1- B13.
D4. A computer program product comprising computer-executable instructions that, when executed by processing circuitry of a network node configured to receive uplink (UL) transmission of data via a plurality of transmission reception points (TRPs) in a wireless network, configure the network node to perform operations corresponding to any of the methods of embodiments B1-B13.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/066291 | 6/16/2021 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63041408 | Jun 2020 | US |
