Patent Application
20240080843
The present disclosure relates to Medium Access Control (MAC) Control Element (CE) signaling and, more specifically, utilization of MAC CEs for mapping of activated Transmission Configuration Indicator (TCI) states and codepoints.
The Fifth Generation (5G) mobile wireless communication system or New Radio (NR) supports a diverse set of use cases and a diverse set of deployment scenarios.
NR uses Cyclic Prefix Orthogonal Frequency Division Multiplexing (OFDM), or CP-OFDM, in the downlink (i.e., from a network node, gNB, eNB, or base station, to a user equipment (UE)) and both CP-OFDM and Discrete Fourier Transform (DFT)-spread OFDM, or DFT-S-OFDM, in the uplink (i.e., from UE to gNB). In the time domain, NR downlink and uplink physical resources are organized into equally-sized subframes of 1 millisecond (ms) each. A subframe is further divided into multiple slots of equal duration.
The slot length depends on subcarrier spacing. For subcarrier spacing of Δf=15 kHz, there is only one slot per subframe and each slot always consists of 14 OFDM symbols, irrespectively of the subcarrier spacing.
Typical data scheduling in NR are per slot basis. An example is shown in
Different subcarrier spacing values are supported in NR. The supported subcarrier spacing values (also referred to as different numerologies) are given by Δf=(15×2α) kHz where a is a non-negative integer. Δf=15 kHz is the basic subcarrier spacing that is also used in Long Term Evolution (LTE). The slot durations at different subcarrier spacings are shown in Table 1.
In the frequency-domain physical resource definition, a system bandwidth is divided into Resource Blocks (RBs), each corresponding to twelve contiguous subcarriers. The Common RBs (CRBs) are numbered starting with 0 from one end of the system bandwidth. The UE is configured with one or up to four bandwidth parts (BWPs), which may be a subset of the RBs supported on a carrier. Hence, a BWP may start at a CRB larger than zero. All configured BWPs have a common reference, which is the CRB 0. Hence, a UE can be configured a narrow BWP (e.g., 10 Megahertz (MHz)) and a wide BWP (e.g., 100 MHz), but only one BWP can be active for the UE at a given point in time. The Physical RBs (PRB) are numbered from 0 to N−1 within a BWP, but note that the 0:th PRB of a BWP may be the K:th CRB where K>0.
Downlink transmissions can be dynamically scheduled, i.e., in each slot the gNB transmits Downlink Control Information (DCI) over PDCCH about which UE data is to be transmitted to and which RBs in the current downlink slot the data is transmitted on. PDCCH is typically transmitted in the first one or two OFDM symbols in each slot in NR. The UE data is carried on PDSCH. A UE first detects and decodes PDCCH and, if the decoding is successful, it then decodes the corresponding PDSCH based on the decoded DCI in the PDCCH.
Uplink data transmission can also be dynamically scheduled using PDCCH. Similar to downlink, a UE first decodes uplink grants in PDCCH and then transmits data over PUSCH based the decoded control information in the uplink grant such as modulation order, coding rate, uplink resource allocation, etc.
In NR, several signals can be transmitted from different antenna ports of a same base station. These signals can have the same large-scale properties such as Doppler shift/spread, average delay spread, or average delay. These antenna ports are then said to be Quasi Co-Located (QCL).
If 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 apply that estimate for receiving signal on the other antenna port.
For example, there may be a QCL relation between a Channel State Information Reference Signal (CSI-RS) for Tracking RS (TRS) and the PDSCH Demodulation Reference Signal (DMRS). When UE receives the PDSCH DMRS, the UE can use the measurements already made on the TRS to assist the DMRS reception.
Information about what assumptions can be made regarding QCL is signaled to the UE from the network. In NR, four types of QCL relations between a transmitted source RS and transmitted target RS were defined:
QCL type D was introduced to facilitate beam management with analog beamforming and is known as spatial QCL. There is currently no strict definition of spatial QCL, but the understanding is that if two transmitted antenna ports are spatially QCL, the UE can use the same receive (Rx) beam to receive them. This is helpful for a UE that uses analog beamforming to receive signals, since the UE needs to adjust its Rx beam in some direction prior to receiving a certain signal. If the UE knows that the signal is spatially QCL with some other signal it has received earlier, then it can safely use the same Rx beam to also receive this signal. Note that for beam management, the discussion mostly revolves around QCL Type D, but it is also necessary to convey a Type A QCL relation for the RSs to the UE, so that it can estimate all the relevant large-scale parameters.
Typically, this is achieved by configuring the UE with a CSI-RS for tracking (TRS) 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 means that the TRS must be transmitted in a suitable beam to a certain UE.
To introduce dynamics in beam and Transmission and Reception point (TRP) selection, the UE can be configured through Radio Resource Control (RRC) signaling with up to 128 Transmission Configuration Indicator (TCI) states.
Each TCI state contains QCL information related to one or two RSs. For example, a TCI state may contain CSI-RS1 associated with QCL Type A and CSI-RS2 associated with QCL TypeD. If a third RS, e.g. the PDCCH DMRS, has this TCI state as QCL source, it means that the UE can derive Doppler shift, Doppler spread, average delay, delay spread from CSI-RS1 and Spatial Rx parameter (i.e., the RX beam to use) from CSI-RS2 when performing the channel estimation for the PDCCH DMRS.
A first list of available TCI states is configured for PDSCH, and a second list of TCI states is configured for PDCCH. Each TCI state contains a pointer, known as TCI State ID, which points to the TCI state. The network then activates, via a Medium Access Control (MAC) Control Element (CE), one TCI state for PDCCH (i.e., provides a TCI for PDCCH) and up to eight TCI states for PDSCH. The number of active TCI states that the UE supports is a UE capability, but the maximum in the current NR specifications is eight.
Assume a UE has four activated TCI states (from a list of 64 configured TCI states). Hence, sixty TCI states are inactive for this particular UE, and the UE needs not be prepared to have large scale parameters estimated for those inactive TCI states. But the UE continuously tracks and updates the large-scale parameters for the RSs in the four active TCI states. When scheduling a PDSCH to a UE, the DCI contains a pointer to one activated TCI state. The UE then knows which large-scale parameter estimate to use when performing PDSCH DMRS channel estimation and thus PDSCH demodulation.
As long as the UE can use any of the currently activated TCI states, it is sufficient to use DCI signaling. However, at some point in time, none of the RSs in the currently activated TCI states can be received by the UE, i.e., when the UE moves out of the beams in which the RSs in the activated TCI states are transmitted. When this happens (or actually before this happens), the gNB would have to activate new TCI states. Typically, since the number of activated TCI states is fixed, the gNB would also have to deactivate one or more of the currently activated TCI states.
Now the details of the MAC CE signaling that is used to activate/deactivate TCI states for UE specific PDSCH are provided.
As shown in
Note that the TCI States Activation/Deactivation for UE-specific PDSCH MAC CE is identified by a MAC PDU subheader with Logical Channel ID (LCID) as specified in Table 6.2.1-1 of 3GPP TS 38.321, NR; MAC protocol specification, V16.2.1, (10-2020). The MAC CE for Activation/Deactivation of TCI States for UE-specific PDSCH has variable size.
The gNB can use DCI format 1_1 or 1_2 to indicate to the UE that it shall use one of the activated TCI states for the subsequent PDSCH reception. The field being used in the DCI is Transmission configuration indication, which is 3 bits if td-PresentInDCI is “enabled” or td-PresentForDCI-Format1-2-r16 is present respectively for DCI format 1_1 and DCI 1_2 by higher layer.
DCI code point 0 indicates the first TCI state index in the list of TCI states, DCI code point 1 indicates the second TCI state index in the list, and so on.
In NR Rel-16, multi-DCI scheduling is for multi-TRP in which a UE may receive two DCIs each scheduling a PDSCH/PUSCH. Each PDCCH and PDSCH are transmitted from the same TRP.
For multi-DCI operation, a UE needs to be configured with two CORESET pools, each associated with a TRP. Each CORESET pool is a collection of CORESETs that belongs to the same pool. A CORESET pool index can be configured in each CORESET with a value of 0 or 1. For the two DCIs in the above example, they are transmitted in two CORESETs belonging to different CORESET pools (i.e., with CORESETPoolIndex 0 and 1 respectively).
In Release 16, single-DCI based multi-TRP operation was also specified. In single-DCI based multi-TRP operation, two DL TCI states are associated to one DCI codepoint. That is, when a TCI field codepoint in DCI indicates two TCI states, each TCI state corresponds to a different beam or different TRP. The activation and mapping of 2 TCI states for a codepoint in the TCI field of DCI is done with the MAC CE in clause 6.1.3.24 from 3GPP TS 38.321.
Embodiments of a method of activating downlink Transmission Configuration Indication (TCI) states and/or uplink TCI states using a single Medium Access Control (MAC) Control Element (CE) are disclosed. In one embodiment, the method comprises the MAC CE mapping the activated downlink (DL) TCI states and/or uplink (UL) TCI states to a plurality of codepoints of a TCI field of a Downlink Control Information (DCI). A particular codepoint among the plurality of codepoints of the TCI field of the DCI is mapped via the MAC CE to only downlink TCI state(s), only uplink TCI state(s), or to both downlink TCI states and uplink TCI states. Accordingly, embodiments of the present disclosure provide efficient and flexible mechanisms to associate TCI state(s) associated with a codepoint of a TCI field in DCI, therefore results in low signaling overhead for activating DL and/or UL TCI states to a UE.
There are, proposed herein, various embodiments which address one or more of the issues disclosed herein. Embodiments of a method performed by a wireless communication device (WCD) (e.g., a UE) are disclosed herein. In one embodiment, a method performed by a WCD comprises receiving, from a RAN node, a MAC CE that comprises information that: (a) indicates a plurality of activated TCI states for the WCD comprising at least one DL TCI state and at least one UL TCI state and (b) maps each activated TCI state of the plurality of activated TCI states to one of a plurality of codepoints of a TCI field in a DCI.
In one embodiment, the method further comprises receiving a DCI comprising a TCI field set to a particular codepoint of the plurality of codepoints of the TCI field and determining, from the plurality of activated TCI states, a TCI state to be used for reception of a downlink transmission or transmission of an uplink transmission based on the particular codepoint of the TCI field comprised in the received DCI. In one embodiment, the method further comprises performing reception of the downlink transmission or transmission of the uplink transmission based on the determined TCI state.
In one embodiment, for at least one codepoint of the plurality of codepoints of the TCI field, the information comprised in the MAC CE maps an equal number of DL TCI states and UL TCI states to the at least one codepoint. In one embodiment, the equal number of DL TCI states and UL TCI states is one DL TCI state and one UL TCI state. In one embodiment, the information comprised in the MAC CE maps the equal number of DL TCI states and UL TCI states to the at least one codepoint for one Component Carrier (CC)/DL Bandwidth Part (BWP), a set of CCs/DL BWPs, one CC/UL BWP, or a set of CCs/DL BWPs and CCs/UL BWPs. In one embodiment, the information comprised in the MAC CE maps the equal number of DL TCI states and UL TCI states to the at least one codepoint for the set of CCs/DL BWPs or the set of CCs/DL BWPs and CCs/UL BWPs, and the equal number of DL TCI states and UL TCI states are applied to each DL BWP in the set of CCs/DL BWPs or the set of CCs/DL BWPs and CCs/UL BWPs.
In another embodiment, the equal number of DL TCI states and UL TCI states is two DL TCI states and two UL TCI states.
In one embodiment, for at least one codepoint of the plurality of codepoints of the TCI field, the information comprised in the MAC CE maps different numbers of DL TCI states and UL TCI states to the at least one codepoint. In one embodiment, the different numbers of DL TCI states and UL TCI states is two DL TCI states and one UL TCI state. In one embodiment, the two DL TCI states respectively correspond to two beams received from two Transmission/Reception Points, TRPs, in DL, and wherein the one UL TCI state corresponds to a beam transmitted towards one TRP in UL.
In another embodiment, the different numbers of DL TCI states and UL TCI states is one DL TCI state and two UL TCI states. In one embodiment, the one DL TCI states corresponds to a beam received from a TRPs in DL, and wherein the two UL TCI states respectively correspond to two beams transmitted towards two TRPs in UL.
In one embodiment, for at least one codepoint of the plurality of codepoints of the TCI field, the information comprised in the MAC CE maps either one or more DL TCI states or one or more UL TCI states, but not both DL and UL TCI states, to the at least one codepoint.
In one embodiment, the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field, one or more bits fields comprising: a first bit field where one bit in the first bit field indicates whether the codepoint is mapped to a first DL TCI state, a second bit field where one bit in the second bit field indicates whether the codepoint is mapped to a second DL TCI state, a third bit field where one bit in the third bit field indicates whether the codepoint is mapped to a first UL TCI state, a fourth bit field where one bit in the fourth bit field indicates whether the codepoint is mapped to a second UL TCI state, or a combination of any two or more of the first, second, third, and fourth bit fields.
In one embodiment, for at least one codepoint of the plurality of codepoints of the TCI field, the WCD is configured with information that indicates a number of DL TCI states to which the codepoint is mapped, information that indicates a number of UL TCI states to which the codepoint is mapped, or both.
In one embodiment, the particular codepoint is mapped to a single DL TCI state in the MAC CE, and the single DL TCI state is applied for all CORESETs configured to the WCD. In another embodiment, the particular codepoint is mapped to a single DL TCI state in the MAC CE, and the single DL TCI state is applied for a subset of all CORESETs configured to the WCD. In another embodiment, the particular codepoint is mapped to two DL TCI states in the MAC CE, a single CORESET is configured for the WCD, and one of the two DL TCI states is applied to the single CORESET. In another embodiment, the particular codepoint is mapped to two DL TCI states in the MAC CE, a single CORESET is configured for the WCD, and both of the two DL TCI states are applied to the single CORESET.
In another embodiment, the particular codepoint is mapped to two (or more) DL TCI states in the MAC CE, two (or more) CORESETs are configured for the WCD, and the two (or more) DL TCI states are applied to the two (or more) CORESETs in a predefined pattern. In another embodiment, the particular codepoint is mapped to two (or more) DL TCI states in the MAC CE, two (or more) CORESETs are configured for the WCD, and all of the two (or more) DL TCI states are applied to each of the two (or more) CORESETs.
In one embodiment, the particular codepoint is mapped to a single UL TCI state in the MAC CE, a PUCCH resource was activated with a single UL TCI state, and the single UL TCI state activated for the PUCCH resource is updated with the single UL TCI state mapped to the particular codepoint in the MAC CE. In another embodiment, the particular codepoint is mapped to a single UL TCI state in the MAC CE, a PUCCH resource was activated with two (or more) UL TCI states, and one of the two (or more) UL TCI states activated for the PUCCH resource is updated with the single UL TCI state mapped to the particular codepoint in the MAC CE.
In one embodiment, the particular codepoint is mapped to a two (or more) UL TCI states in the MAC CE, one of the two (or more) UL TCI states is mapped to SRS resources in a first SRS resource set and another of the two (or more) UL TCI states is mapped to SRS resources in a second SRS resource set. In one embodiment, the first and second SRS resource sets are configured for codebook or non-codebook based PUSCH transmissions.
In one embodiment, the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field: one or more first TCI state IDs that indicate one or more activated DL TCI states mapped to the codepoint and one or more second TCI state IDs that indicate one or more activated UL TCI states mapped to the codepoint.
In one embodiment, at least one DL TCI state is mapped to each codepoint of the plurality of codepoints of the TCI field, and the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field: a first bit field that indicates whether a second DL TCI state is mapped to the codepoint in the MAC CE, a second bit field that indicates whether a first UL TCI state is mapped to the codepoint in the MAC CE, and a third bit field that indicates whether a second UL TCI state is mapped to the codepoint in the MAC CE.
In one embodiment, at least one DL TCI state and at least one UL TCI state are mapped to each codepoint of the plurality of codepoints of the TCI, and the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field, a first bit field that indicates whether a second DL TCI state is mapped to the codepoint in the MAC CE and a second bit field that indicates whether a second UL TCI state is mapped to the codepoint in the MAC CE.
In one embodiment, at least one DL TCI state is mapped to each codepoint of the plurality of codepoints of the TCI field, and the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field: a first bit field that indicates whether a first DL TCI state is mapped to the codepoint in the MAC CE, a second bit field that indicates whether a second DL TCI state is mapped to the codepoint in the MAC CE, a third bit field that indicates whether a first UL TCI state is mapped to the codepoint in the MAC CE, and a fourth bit field that indicates whether a second UL TCI state is mapped to the codepoint in the MAC CE.
Corresponding embodiments of a WCD are also disclosed. In one embodiment, a WCD is adapted to receive, from a RAN node, a MAC CE that comprises information that: (a) indicates a plurality of activated TCI states for the WCD comprising at least one DL TCI state and at least one UL TCI state and (b) maps each activated TCI state of the plurality of activated TCI states to one of a plurality of codepoints of a TCI field in a DCI.
In another embodiment, a WCD comprises one or more transmitters, one or more receivers, and processing circuitry associated with the one or more transmitters and the one or more receivers. The processing circuitry is configured to cause the WCD to receive, from a RAN node, a MAC CE that comprises information that: (a) indicates a plurality of activated TCI states for the WCD comprising at least one DL TCI state and at least one UL TCI state and (b) maps each activated TCI state of the plurality of activated TCI states to one of a plurality of codepoints of a TCI field in a DCI.
Embodiments of a method performed by a RAN node are also disclosed. In one embodiment, a method performed by a RAN node comprises sending, to a WCD, a MAC CE that comprises information that: (a) indicates a plurality of activated TCI states for the WCD comprising at least one DL TCI state and at least one UL TCI state and (b) maps each activated TCI state of the plurality of activated TCI states to one of a plurality of codepoints of a TCI field in a DCI.
In one embodiment, the method further comprises sending, to the WCD, a DCI comprising a TCI field set to a particular codepoint of the plurality of codepoints of the TCI field.
In one embodiment, for at least one codepoint of the plurality of codepoints of the TCI field, the information comprised in the MAC CE maps an equal number of DL TCI states and UL TCI states to the at least one codepoint. In one embodiment, the equal number of DL TCI states and UL TCI states is one DL TCI state and one UL TCI state. In one embodiment, the information comprised in the MAC CE maps the equal number of DL TCI states and UL TCI states to the at least one codepoint for one CC/DL BWP, a set of CCs/DL BWPs, one CC/UL BWP, or a set of CCs/DL BWPs and CCs/UL BWPs. In one embodiment, the information comprised in the MAC CE maps the equal number of DL TCI states and UL TCI states to the at least one codepoint for the set of CCs/DL BWPs or the set of CCs/DL BWPs and CCs/UL BWPs, and the equal number of DL TCI states and UL TCI states are applied to each DL BWP in the set of CCs/DL BWPs or the set of CCs/DL BWPs and CCs/UL BWPs.
In another embodiment, the equal number of DL TCI states and UL TCI states is two DL TCI states and two UL TCI states.
In one embodiment, for at least one codepoint of the plurality of codepoints of the TCI field, the information comprised in the MAC CE maps different numbers of DL TCI states and UL TCI states to the at least one codepoint. In one embodiment, the different numbers of DL TCI states and UL TCI states is two DL TCI states and one UL TCI state. In another embodiment, the different numbers of DL TCI states and UL TCI states is one DL TCI state and two UL TCI states.
In one embodiment, for at least one codepoint of the plurality of codepoints of the TCI field, the information comprised in the MAC CE maps either one or more DL TCI states or one or more UL TCI states, but not both DL and UL TCI states, to the at least one codepoint.
In one embodiment, the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field, one or more bits fields comprising: a first bit field where one bit in the first bit field indicates whether the codepoint is mapped to a first DL TCI state, a second bit field where one bit in the second bit field indicates whether the codepoint is mapped to a second DL TCI state, a third bit field where one bit in the third bit field indicates whether the codepoint is mapped to a first UL TCI state, a fourth bit field where one bit in the fourth bit field indicates whether the codepoint is mapped to a second UL TCI state, or a combination of any two or more of the first, second, third, and fourth bit fields.
In one embodiment, for at least one codepoint of the plurality of codepoints of the TCI, the WCD is configured with information that indicates a number of DL TCI states to which the codepoint is mapped, information that indicates a number of UL TCI states to which the codepoint is mapped, or both.
In one embodiment, the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field: one or more first TCI state IDs that indicate one or more activated DL TCI states mapped to the codepoint and one or more second TCI state IDs that indicate one or more activated UL TCI states mapped to the codepoint.
In one embodiment, at least one DL TCI state is mapped to each codepoint of the plurality of codepoints of the TCI field, and the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field: a first bit field that indicates whether a second DL TCI state is mapped to the codepoint in the MAC CE, a second bit field that indicates whether a first UL TCI state is mapped to the codepoint in the MAC CE, and a third bit field that indicates whether a second UL TCI state is mapped to the codepoint in the MAC CE.
In one embodiment, at least one DL TCI state and at least one UL TCI state are mapped to each codepoint of the plurality of codepoints of the TCI field, and the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field: a first bit field that indicates whether a second DL TCI state is mapped to the codepoint in the MAC CE and a second bit field that indicates whether a second UL TCI state is mapped to the codepoint in the MAC CE.
In one embodiment, at least one DL TCI state is mapped to each codepoint of the plurality of codepoints of the TCI field, and the information comprised in the MAC CE comprises, for each codepoint of the plurality of codepoints of the TCI field: a first bit field that indicates whether a first DL TCI state is mapped to the codepoint in the MAC CE, a second bit field that indicates whether a second DL TCI state is mapped to the codepoint in the MAC CE, a third bit field that indicates whether a first UL TCI state is mapped to the codepoint in the MAC CE, and a fourth bit field that indicates whether a second UL TCI state is mapped to the codepoint in the MAC CE.
Corresponding embodiments of a RAN node are also disclosed. In one embodiment, a RAN node is adapted to send, to a WCD, a MAC CE that comprises information that: (a) indicates a plurality of activated TCI states for the WCD comprising at least one DL TCI state and at least one UL TCI state and (b) maps each activated TCI state of the plurality of activated TCI states to one of a plurality of codepoints of a TCI field in a DCI.
In one embodiment, a RAN node comprises processing circuitry configured to cause the RAN node to send, to a WCD, a MAC CE that comprises information that: (a) indicates a plurality of activated TCI states for the WCD comprising at least one DL TCI state and at least one UL TCI state and (b) maps each activated TCI state of the plurality of activated TCI states to one of a plurality of codepoints of a TCI field in a DCI.
The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure.
The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure.
Radio Node: As used herein, a “radio node” is either a radio access node or a wireless communication device.
Radio Access Node: As used herein, a “radio access node” or “radio network node” or “radio access network node” or “RAN node” is any node in a Radio Access Network (RAN) of a cellular communications network that operates to wirelessly transmit and/or receive signals. Some examples of a radio access node include, but are not limited to, a base station (e.g., a New Radio (NR) base station (gNB) in a Third Generation Partnership Project (3GPP) Fifth Generation (5G) NR network or an enhanced or evolved Node B (eNB) in a 3GPP Long Term Evolution (LTE) network), a high-power or macro base station, a low-power base station (e.g., a micro base station, a pico base station, a home eNB, or the like), a relay node, a network node that implements part of the functionality of a base station (e.g., a network node that implements a gNB Central Unit (gNB-CU) or a network node that implements a gNB Distributed Unit (gNB-DU)) or a network node that implements part of the functionality of some other type of radio access node.
Core Network Node: As used herein, a “core network node” is any type of node in a core network or any node that implements a core network function. Some examples of a core network node include, e.g., a Mobility Management Entity (MME), a Packet Data Network Gateway (P-GW), a Service Capability Exposure Function (SCEF), a Home Subscriber Server (HSS), or the like. Some other examples of a core network node include a node implementing an Access and Mobility Management Function (AMF), a User Plane Function (UPF), a Session Management Function (SMF), an Authentication Server Function (AUSF), a Network Slice Selection Function (NSSF), a Network Exposure Function (NEF), a Network Function (NF) Repository Function (NRF), a Policy Control Function (PCF), a Unified Data Management (UDM), or the like.
Communication Device: As used herein, a “communication device” is any type of device that has access to an access network. Some examples of a communication device include, but are not limited to: mobile phone, smart phone, sensor device, meter, vehicle, household appliance, medical appliance, media player, camera, or any type of consumer electronic, for instance, but not limited to, a television, radio, lighting arrangement, tablet computer, laptop, or Personal Computer (PC). The communication device may be a portable, hand-held, computer-comprised, or vehicle-mounted mobile device, enabled to communicate voice and/or data via a wireless or wireline connection.
Wireless Communication Device: One type of communication device is a wireless communication device, which may be any type of wireless device that has access to (i.e., is served by) a wireless network (e.g., a cellular network). Some examples of a wireless communication device include, but are not limited to: a User Equipment device (UE) in a 3GPP network, a Machine Type Communication (MTC) device, and an Internet of Things (IoT) device. Such wireless communication devices may be, or may be integrated into, a mobile phone, smart phone, sensor device, meter, vehicle, household appliance, medical appliance, media player, camera, or any type of consumer electronic, for instance, but not limited to, a television, radio, lighting arrangement, tablet computer, laptop, or PC. The wireless communication device may be a portable, hand-held, computer-comprised, or vehicle-mounted mobile device, enabled to communicate voice and/or data via a wireless connection.
Network Node: As used herein, a “network node” is any node that is either part of the RAN or the core network of a cellular communications network/system.
Transmission/Reception Point (TRP): In some embodiments, a TRP may be either a network node, a radio head, a spatial relation, or a Transmission Configuration Indicator (TCI) state. A TRP may be represented by a spatial relation or a TCI state in some embodiments. In some embodiments, a TRP may be using multiple TCI states.
In 3GPP Rel-17, a new enhanced TCI state framework will be specified. Specifically, in 3GPP Technical Specification Group (TSG) RAN WG1 e-meeting RAN1 #103-e, it was agreed that the new TCI state framework should include a three stage TCI state indication (in a similar way as was described above for Physical Downlink Shared Channel (PDSCH)) for all or a subset of all downlink and/or uplink channels/signals. In the first stage, RRC is used to configure a pool of TCI states. In the second stage, one or more of the Radio Resource Control (RRC) configured TCI states are activated via Medium Access Control (MAC)-Control Element (CE) signaling. Finally, in the third stage, Downlink Control Information (DCI) signaling is used to select one of the TCI states that was activated via MAC-CE. The TCI states used for downlink (DL) and uplink (UL) channels/signals can either be taken from the same pool of TCI states or from separate pools of TCI states (i.e., from separate downlink TCI state and uplink TCI state pools). It is also possible that two separate lists of activated TCI states are used, one for downlink channels/signals and one for uplink channels/signals.
Some agreements from the RAN1 #103-e e-meeting is copied below:
There currently exist certain challenge(s). In NR Rel-17, it is agreed that downlink DCI is used to indicate a beam update (i.e., TCI state update). The TCI states will be activated by MAC CE and mapped to TCI field codepoints in downlink DCI. Furthermore, both downlink TCI states and uplink TCI states will be supported in New Radio (NR) Rel-17. An open problem is how MAC CE signals the activation and mapping of downlink and uplink TCI states to the codepoints of a downlink DCI.
Certain aspects of the present disclosure and their embodiments may provide solutions to the aforementioned or other challenges. Systems and methods are disclosed herein that provide a way to activate downlink and/or uplink TCI states for different DCI codepoints using a MAC CE. Embodiments of the present disclosure include various MAC CE designs that provide such a mapping.
Certain embodiments of the present disclosure may provide one or more of the following technical advantage(s). The proposed MAC CE signaling solutions provide efficient and flexible mechanisms to associate one or multiple DL and/or UL TCI state(s) associated with a codepoint of a TCI field in DCI. The proposed solution results in low signaling overhead for activating DL and/or UL TCI states to a UE.
Note that the description given 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.
Note that, in the description herein, reference may be made to the term “cell;” however, particularly with respect to 5G NR concepts, beams may be used instead of cells and, as such, it is important to note that the concepts described herein are equally applicable to both cells and beams.
The base stations 702 and the low power nodes 706 provide service to wireless communication devices 712-1 through 712-5 in the corresponding cells 704 and 708. The wireless communication devices 712-1 through 712-5 are generally referred to herein collectively as wireless communication devices 712 and individually as wireless communication device 712. In the following description, the wireless communication devices 712 are oftentimes UEs, but the present disclosure is not limited thereto.
A UE is configured by a gNB with one or more of a list of DL TCI states and a list of UL TCI states. The TCI states in the list of DL TCI states are applicable to DL channels such as, e.g., Physical Downlink Control Channel (PDCCH) and PDSCH and DL reference signals such as, e.g., Channel State Information (CSI)-Reference Signal (RS). The TCI states in the list of UL TCI states are applicable to UL channels such as, e.g., PUCCH and Physical Uplink Shared Channel (PUSCH) and UL reference signals such as, e.g., Sounding Reference Signal (SRS).
In one embodiment, a single MAC CE is used to activate DL TCI states and/or UL TCI states. The MAC CE also maps the activated DL TCI states and/or the activated UL TCI states to a plurality of codepoints in a TCI field of a DCI. For instance, the DCI here may be a downlink DCI with format 1_1 or 1_2.
A particular codepoint, referred to as codepoint x, among the plurality of codepoints of the TCI field of the DCI is mapped via the MAC CE to both one or more activated DL TCI states and one or more activated UL TCI states. When the UE receives a DCI where the TCI field indicates the codepoint x, the UE can perform the following procedures:
In one embodiment, in a single TRP case where a UE may receive DL channels/reference signals using a first beam corresponding to a first DL TCI state and transmit UL channels/reference signals using a second beam corresponding to a first UL TCI state, a codepoint x among the plurality of codepoints in the TCI field of the DCI is mapped via the MAC CE to one DL TCI state and one UL TCI state. For example, as described with regards to
For the single-DCI based multi-TRP case, the DL channels/reference signals received using the first beam corresponding to the first DL TCI state may be transmitted from a first TRP, whereas the UL channels/reference signals transmitted using a second beam corresponding to a first UL TCI state may be transmitted towards a second TRP.
In another embodiment, in a case where a UE receives DL channels/reference signals from two TRPs in the DL and transmits UL channels/reference signals towards two TRPs in the UL, a codepoint x among the plurality of codepoints in the TCI field of the DCI is mapped via the MAC CE to two DL TCI states and two UL TCI states. Here, the two DL TCI states corresponds to two beams received from two TRPs in the DL, and the two UL TCI states corresponds to two beams transmitted towards two TRPs in the UL.
In one embodiment, in a case where a UE receives DL channels/reference signals from two TRPs in the DL and transmits UL channels/reference signals towards a single TRP, a codepoint x among the plurality of codepoints in the TCI field of the DCI is mapped via the MAC CE to two DL TCI states and one UL TCI state. Here, the two DL TCI states correspond to two beams received from two TRPs in the DL, and the UL TCI state corresponds to a beam transmitted towards one TRP in the UL.
In another embodiment, in a case where a UE receives DL channels/reference signals from one TRP in the DL and transmits UL channels/reference signals towards two TRPs in the UL, a codepoint x among the plurality of codepoints in the TCI field of the DCI is mapped via the MAC CE to one DL TCI state and two UL TCI states. Here, the one DL TCI state corresponds to one beam received from one TRP in the DL, and the two UL TCI states corresponds to two beams transmitted towards two TRPs in the UL.
In some cases, it may be desirable to only update the DL TCI states to be applied to DL channels and/or DL reference signals. In these cases, in one embodiment, a codepoint x among the plurality of codepoints in the TCI field of the DCI is mapped via the MAC CE to either one or two DL TCI states, and no UL TCI state. When the UE receives a DCI where the TCI field indicates the codepoint x, the UE updates the one or two DL TCI state(s) to be applied to DL channels and/or DL reference signals.
In some other cases, it may be desirable to only update the UL TCI states to be applied to UL channels and/or DL reference signals. In these cases, in one embodiment, a codepoint x among the plurality of codepoints in the TCI field of the DCI is mapped via the MAC CE to either one or two UL TCI states, and no DL TCI state. When the UE receives a DCI where the TCI field indicates the codepoint x, the UE updates the one or two UL TCI state(s) to be applied to UL channels and/or UL reference signals.
In the one embodiment, the plurality of codepoints in the TCI field of the DCI may contain different mappings to DL and UL TCI states wherein:
Hence, to support different mappings to different codepoints, the MAC CE needs to contain different bit fields that indicate how many and which DL TCI state(s) and/or UL TCI state(s) are mapped to each codepoint. In one embodiment, for each codepoint, a plurality of binary fields may be present in the MAC CE wherein:
In some embodiments, only a subset of the above bit fields may be present in the MAC CE. In one example embodiment, a given codepoint is always mapped to a first DL TCI state. Whether the given codepoint is mapped to a second DL TCI state, a first UL TCI state, and/or a second UL TCI state is given by three (or N) different bit fields in the MAC CE.
In another embodiment, the abovementioned fields may be predetermined in 3GPP specifications, or be configured via RRC signaling. In this embodiment, the above binary fields do not need to be included as part of the MAC CE. The following are some examples of this embodiment:
An example MAC CE that can be used for embodiments of the present disclosure is as follows.
In this example, the MAC CE has a fixed size. The first field in the first octet may represent the CORESETPoolindex in order the UE to know how to interpret the TCI states. That is, if the DCI was sent to the UE via PDCCH mapped to CORESETPoolIndex=1, the UE uses the mapping of the TCI states received earlier by the UE by a MAC CE which had this field set to ‘1’. Similarly, if the same DCI was received via PDCCH that is mapped to CORESETPoolIndex=0, the UE uses the mapping of the TCI states received earlier by the UE by a MAC CE which had this field set to ‘0’. In this way, the same DCI codepoints may have two different mappings depending via which TRP the PDCCH(DCI) was sent. The advantage of the fixed size MAC CE is that 8 bits may be used for the TCI state ID.
When there is a single DL TCI state associated with a codepoint in the MAC CE and the codepoint is indicated in a DL DCI, in one embodiment, the corresponding DL TCI state is applied to (or activated for) all CORESETs configured to the UE. In another embodiment, the corresponding DL TCI state is applied to a subset of CORESETs, e.g., CORESETS with even (or odd) numbered CORESET indices.
When there are two DL TCI states associated with a codepoint in the MAC CE and the codepoint is indicated in a DL DCI and if only one CORESET is configured for the UE, in one embodiment, the first of the two TCI states is applied to the CORESET. In another embodiment, the CORESET is activated with both of the two TCI states. This corresponds to sending a same DCI over two TRPs in the same time and frequency resource.
When there are two DL TCI states associated with a codepoint in the MAC CE and the codepoint is indicated in a DL DCI and if more than one CORESET are configured for the UE, the mapping between the two activated TCI states and the CORESETs follows a predefined pattern. For example, the first of the two TCI states may be mapped to CORESETs with even (or odd) numbered CORESET indices, and the second of the two TCI states may be mapped to the remaining CORESETs. In a further embodiment, all the CORESETs are activated with both of the two TCI states. In yet another embodiment, if two CORESETs are linked via two linked search space sets, the two CORESETs are activated with the two TCI states, respectively.
In one embodiment, when there is a single UL TCI state associated with a codepoint in the MAC CE and the codepoint is indicated in a DL DCI, if a PUCCH resource was activated with a single UL TCI state, the UL TCI state is updated with the new UL TCI state. If a PUCCH resource was activated with two UL TCI states, in one embodiment, the first (or the second) TCI state is updated with the new UL TCI state.
For UL transmission to two TRPs, two SRS resource sets need to be configured for both codebook and non-codebook based PUSCH transmissions. In one embodiment, when there are two UL TCI states associated with a codepoint in the MAC CE and the codepoint is indicated in a DL DCI, the first of the two TCI states may be mapped to SRS resources in the first SRS resource set with even (or odd) numbered SRS resource set index and the second of the two TCI states may be mapped to SRS resources in the other SRS resource set.
In this embodiment, in one MAC CE, a network node (e.g., a base station 702 such as, e.g., a gNB) can separately indicate the activated DL TCI state(s) and UL TCI state(s). The activated DL TCI state(s) and UL TCI state(s) are mapped to the codepoints of the TCI field in a DCI (e.g., a DL DCI with format 1_1 or 1_2).
In some embodiments, in order for the UE to be able to decode the MAC CE, the structure needs to be known. One option is to hard code or configure (e.g., configure via RRC) the number of potential pairs of DL or UL TCI states and use the length field of the MAC CE. In one example, the number of DL TCI states and the number of UL TCI states per each codepoint may be configured (e.g., configured via RRC). From this configuration information, the UE will know the number of octets needed for signaling the DL TCI states and UL TCI states (i.e., the values M and M′ can be known from this configuration).
In some other examples, the MAC CE can be defined such that it always includes both UL and DL TCI states, and the UE is configured (e.g., RRC configured) on the number of the DL and UL pairs, respectively. Another option is that UE uses the TCI field size in DCI and only the number of DL and UL TCI states is configured (e.g., RRC configured). The configuration (e.g., RRC configuration) may include the number of TCI state codepoints in the TCI field in DCI. This may be configured (e.g., via RRC) for both DL and UL or it may be configured jointly as one value that is applicable to both DL and UL. Then, the UE knows from ‘Cj’ field whether the first DL TCI state follows with another DL TCI state that is a pair to the first TCI state. Then, UE knows if the next TCI state is still DL TCI state followed by a potential pair, or it is an UL TCI state followed by a potential pair (known from ‘Dj’ field). Alternatively, the R field in the first octet may be used to inform the UE whether the MAC CE includes both DL and UL TCI states or only the DL TCI states.
The above embodiments can be extended to Multi-DCI based Multi-TRP scenario. For instance, the R field in the first octet of
In some cases, the number of DL or UL TCI states configured to the UE may be extended to 256 in NR Rel-17. This is because inter-cell multi-TRP will be introduced in NR Rel-17, as such to support TCI states associated with a reference signal in the neighbor cell, the number of DL or UL TCI states may need to be increased. This hence means that each DL TCI state ID or UL TCI state ID needs to be represented by an 8-bit field.
An alternative MAC CE design that allows more than 7 bits also for the flexible size MAC CE can be described as follows. The max 8 bits in the octet 2 may be used to explicitly describe the structure of the following octets. These options may be configured (e.g., RRC configured) or hard coded, e.g., in 3GPP TS 38.321. For example, the bit length of the TCI state fields, possibly UL and DL separately, the number of pairs, which UL/DL TCI state is expected to have a pair and so on. There are 256 codepoints represented by the 8 bits. The UL/DL TCI state field length options could be, e.g., 7, 8, 9, or 10 bits. One option is to use two first bits to represent DL TCI state field length and two following bits to represent the UL TCI state field length. Then one can use 4 following bits to represent the number of pairs. If more than 4 bits are needed, the following octet may be used to describe the combination of UL/DL TCI states given in this MAC CE.
The RAN node 1300 sends a MAC CE (e.g., a single MAC CE) to the WCD 712 that: (a) activates one or more of the configured DL TCI states, activates one or more of the configured UL TCI states, or both activates one or more of the configured DL TCI states and activates one or more of the configured UL TCI states and (b) indicates mappings between the activated DL/UL TCI states and codepoints of a TCI field of a DCI (e.g., for a particular DCI format such as, e.g., DCI format 1_1 or 1_2 in 3GPP NR) (step 13002). The MAC CE may be in accordance with any of the embodiments described above. While the details of all of those embodiments are not repeated here, it is to be understood that the details provided above are applicable the MAC CE of step 13002 as if all of those details were repeated here. For example, in one embodiment, the MAC CE maps at least one codepoint of the TCI field of a DCI to a first number of activated DL TCI states and a second number of activated UL TCI states, where the first and second number may be the same number or different numbers, as described above. As another example, in one embodiment, the MAC CE maps at least one codepoint of the TCI field of a DCI to either one or more activated DL TCI states or one or more activated UL TCI states. As yet another example, the MAC CE may map each of a first subset of the codepoints of the TCI field of a DCI to an equal number of activated DL and UL TCI states, and/or each of a second subset of the codepoints of the TCI field of the DCI to different numbers of activated DL and UL TCI states, and/or each of a third subset of the codepoints of the TCI field of a DCI to either one or more DL TCI states or one or more UL TCI states. In one embodiment, the MAC CE includes indication bit fields as described above in Section I.D. In some embodiments, the activated TCI states are mapped to CORESETs in accordance with Section I.E above. In some embodiments, the activated TCI states are mapped to UL channels and signals in accordance with Section I.F above. In another embodiment, the MAC CE is in accordance with any of the first detailed embodiments described in Section II above. In another embodiment, the MAC CE is in accordance with any of the second detailed embodiments described in Section III above. In another embodiment, the MAC CE is in accordance with any of the third detailed embodiments described in Section IV above.
The WCD 712 receives a DCI (in a PDCCH) from, in this example, the RAN node 1300 (step 13004). The DCI includes a TCI field set to a particular codepoint. The WCD 712 determines the activated DL/UL TCI state(s) to use for downlink reception or uplink transmission of the scheduled downlink transmission or uplink transmission based on the mapping between the particular codepoint of the TCI field in the received DCI and the respective activated DL/UL TCI state(s), as indicated by the MAC CE received in step 13002 (step 13006). The WCD 712 performs downlink reception or uplink transmission in accordance with the determined DL/UL TCI state(s) (step 13008).
As used herein, a “virtualized” RAN node is an implementation of the RAN node 1400 in which at least a portion of the functionality of the RAN node 1400 is implemented as a virtual component(s) (e.g., via a virtual machine(s) executing on a physical processing node(s) in a network(s)). As illustrated, in this example, the RAN node 1400 may include the control system 1402 and/or the one or more radio units 1410, as described above. The control system 1402 may be connected to the radio unit(s) 1410 via, for example, an optical cable or the like. The RAN node 1400 includes one or more processing nodes 1500 coupled to or included as part of a network(s) 1502. If present, the control system 1402 or the radio unit(s) are connected to the processing node(s) 1500 via the network 1502. Each processing node 1500 includes one or more processors 1504 (e.g., CPUs, ASICs, FPGAs, and/or the like), memory 1506, and a network interface 1508.
In this example, functions 1510 of the RAN node 1400 described herein (e.g., one or more functions of a RAN node such as, e.g., the RAN node 1300 described herein) are implemented at the one or more processing nodes 1500 or distributed across the one or more processing nodes 1500 and the control system 1402 and/or the radio unit(s) 1410 in any desired manner. In some particular embodiments, some or all of the functions 1510 of the RAN node 1400 described herein are implemented as virtual components executed by one or more virtual machines implemented in a virtual environment(s) hosted by the processing node(s) 1500. As will be appreciated by one of ordinary skill in the art, additional signaling or communication between the processing node(s) 1500 and the control system 1402 is used in order to carry out at least some of the desired functions 1510. Notably, in some embodiments, the control system 1402 may not be included, in which case the radio unit(s) 1410 communicate directly with the processing node(s) 1500 via an appropriate network interface(s).
In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of RAN node 1400 or a node (e.g., a processing node 1500) implementing one or more of the functions 1510 of the RAN node 1400 in a virtual environment according to any of the embodiments described herein is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).
In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of the wireless communication device 1700 according to any of the embodiments described herein is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).
With reference to
The telecommunication network 1900 is itself connected to a host computer 1916, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server, or as processing resources in a server farm. The host computer 1916 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. Connections 1918 and 1920 between the telecommunication network 1900 and the host computer 1916 may extend directly from the core network 1904 to the host computer 1916 or may go via an optional intermediate network 1922. The intermediate network 1922 may be one of, or a combination of more than one of, a public, private, or hosted network; the intermediate network 1922, if any, may be a backbone network or the Internet; in particular, the intermediate network 1922 may comprise two or more sub-networks (not shown).
The communication system of
Example implementations, in accordance with an embodiment, of the UE, base station, and host computer discussed in the preceding paragraphs will now be described with reference to
The communication system 2000 further includes a base station 2018 provided in a telecommunication system and comprising hardware 2020 enabling it to communicate with the host computer 2002 and with the UE 2014. The hardware 2020 may include a communication interface 2022 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 2000, as well as a radio interface 2024 for setting up and maintaining at least a wireless connection 2026 with the UE 2014 located in a coverage area (not shown in
The communication system 2000 further includes the UE 2014 already referred to. The UE's 2014 hardware 2034 may include a radio interface 2036 configured to set up and maintain a wireless connection 2026 with a base station serving a coverage area in which the UE 2014 is currently located. The hardware 2034 of the UE 2014 further includes processing circuitry 2038, which may comprise one or more programmable processors, ASICs, FPGAs, or combinations of these (not shown) adapted to execute instructions. The UE 2014 further comprises software 2040, which is stored in or accessible by the UE 2014 and executable by the processing circuitry 2038. The software 2040 includes a client application 2042. The client application 2042 may be operable to provide a service to a human or non-human user via the UE 2014, with the support of the host computer 2002. In the host computer 2002, the executing host application 2012 may communicate with the executing client application 2042 via the OTT connection 2016 terminating at the UE 2014 and the host computer 2002. In providing the service to the user, the client application 2042 may receive request data from the host application 2012 and provide user data in response to the request data. The OTT connection 2016 may transfer both the request data and the user data. The client application 2042 may interact with the user to generate the user data that it provides.
It is noted that the host computer 2002, the base station 2018, and the UE 2014 illustrated in
In
The wireless connection 2026 between the UE 2014 and the base station 2018 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 2014 using the OTT connection 2016, in which the wireless connection 2026 forms the last segment. More precisely, the teachings of these embodiments may improve, e.g., latency and/or power consumption and thereby provide benefits such as, e.g., reduced user waiting time, better responsiveness, and/or extended battery lifetime.
A measurement procedure may be provided for the purpose of monitoring data rate, latency, and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 2016 between the host computer 2002 and the UE 2014, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 2016 may be implemented in the software 2010 and the hardware 2004 of the host computer 2002 or in the software 2040 and the hardware 2034 of the UE 2014, or both. In some embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 2016 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which the software 2010, 2040 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 2016 may include message format, retransmission settings, preferred routing, etc.; the reconfiguring need not affect the base station 2018, and it may be unknown or imperceptible to the base station 2018. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer 2002's measurements of throughput, propagation times, latency, and the like. The measurements may be implemented in that the software 2010 and 2040 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 2016 while it monitors propagation times, errors, etc.
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.
While processes in the figures may show a particular order of operations performed by certain embodiments of the present disclosure, it should be understood that such order is exemplary (e.g., alternative embodiments may perform the operations in a different order, combine certain operations, overlap certain operations, etc.).
At least some of the following abbreviations may be used in this disclosure. If there is an inconsistency between abbreviations, preference should be given to how it is used above. If listed multiple times below, the first listing should be preferred over any subsequent listing(s).
Those skilled in the art will recognize improvements and modifications to the embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein.
This application claims the benefit of provisional patent application Ser. No. 63/132,091, filed Dec. 30, 2020, the disclosure of which is hereby incorporated herein by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2021/062495 | 12/30/2021 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63132091 | Dec 2020 | US |
