The present disclosure relates to the field of wireless communications, and in particular to methods and apparatuses for uplink beam management and power control in a wireless network suitable for 5G.
In millimeter wave (mmWave) frequencies (frequency range 2 (FR2)), i.e., frequencies above 6 GHZ, in general, wireless communication between communication devices is performed with spatially selective/directive transmissions and receptions called beams. Therefore, beam management is a required framework for link establishment, adaptation and recovery at FR2.
In the Third Generation Partnership Project Release 15, (3GPP Rel. 15) [1-6], beam management in uplink (UL) is handled separately for various UL channels and UL reference signals. The functionalities of the UL beam management framework are spread over three communication layers—the physical (PHY) layer [1-4], the medium access control (MAC) layer [5] and the Radio Resource Control (RRC) layer [6]. In order to enable a beamformed uplink transmission between a User Equipment (UE) and a radio network node (gNB), the beam management performs two tasks: Indication of the beam direction for the UL transmission, and indication of the transmit power settings associated with it. The two tasks are handled in different ways for the physical uplink shared channel (PUSCH), the physical uplink control channel (PUCCH) and the sounding reference signal (SRS).
On the other hand, in the downlink (DL), the UE must be given directives to derive various parameters such as delay spread, average delay, Doppler and Rx beam direction for the reception of a DL channel or reference signal (RS).
In the following, a brief description of indicating DL transmissions to the UE in 3GPP Rel. 15 is provided. It is followed by an overview of the UL channels and reference signals (RSs) and the corresponding beam configurations and indication mechanisms for the same used in 3GPP Rel. 15. These descriptions of the state of the art (SoTA) lead to the discussion on the inadequacies in UL beam direction and power control indication and configuration mechanisms in 3GPP Rel. 15 that provide the motivation for the present invention.
The term ‘beam’ is used in the following to denote a spatially selective/directive transmission or reception which is achieved by precoding and filtering the outgoing or incoming signal, respectively, at the antenna ports of the device with a particular set of coefficients. The set of coefficients used to spatially direct a transmission/reception in a certain direction may differ from one direction to another direction. The term ‘Tx beam’ denotes a spatially selective/directive transmission and the term ‘Rx beam’ denotes a spatially selective/directive reception. The set of coefficients used to precode/filter the transmission or reception is denoted by the term ‘spatial filter’. The term ‘spatial filter’ is used interchangeably with the term ‘beam direction’ in this disclosure as the spatial filter coefficients determine the direction in which a transmission/reception is spatially directed to.
The physical downlink control channel (PDCCH) and the physical downlink shared channel (PDSCH) carry DL control information and DL data, respectively, to a UE [1-6].
The PDCCH is configured at the Radio Resource Control (RRC) layer level by a base station or a network node or gNodeB (gNB). The gNB transmits the PDCCH(s) on one or more Control Resource Sets (CORESETs) that are configured at RRC level. A CORESET is a set of resource blocks carrying control information. Each CORESET comprises one or more PDCCH(s), each linked to a search space configuration. A PDCCH is either part of a common search space (CSS) or a UE-specific search space (USS). PDCCHs belonging to the CSS usually contain information that is broadcast by the gNB to all UEs, like system information broadcast or paging information. The PDCCHs belonging to a USS contain UE specific information, such as the downlink control information (DCI) to schedule a PDSCH or PUSCH or SRS trigger, etc.
Demodulation Reference Signals (DMRS) are embedded for the coherent demodulation of the PDCCH/PDSCH at the UE. The DMRS consists of a set of DMRS ports. The number of DMRS ports determines the number of transmission layers contained in a PDSCH. DMRS is used for channel estimation at the UE to coherently demodulate the PDSCH or PDCCH(s). In the case of PDCCH, one or more of them may be transmitted on a CORESET. Therefore, the DMRS for the coherent demodulation of the PDCCH(s) on the CORESET may be embedded across the PDCCH(s) transmitted on the CORESET.
An important parameter in the transmission of the PDCCH and the PDSCH is the ‘Transmission Configuration Indication’-state (TCI-state) [4]. In 3GPP Rel. 15, the indication of how the control or the shared channel is transmitted by the gNB and what assumptions the UE must consider while receiving them is done via reference signals (RSs). The indication to the UE is performed using a TCI-state information element (IE) configured via RRC, as shown in
The TCI-state is used to mention how to receive a PDSCH or the PDCCH(s) transmitted on a CORESET. Applying a TCI-state to a PDSCH or CORESET implies that the DMRS ports of the PDSCH or the DMRS ports of the PDCCH(s), transmitted on the CORESET, shall be assumed to be quasi-colocated with the reference signals mentioned in the TCI-state according to the corresponding quasi-colocation assumptions for the reference signal mentioned in the TCI-state.
Assuming ‘quasi-colocation’ means that certain channel parameters such as Doppler shift/spread, delay spread, average delay and/or Tx beam direction are assumed to be the same for the DL RS mentioned in the TCI-state and the DMRS ports of the PDSCH, or the DMRS ports of the PDCCH(s) transmitted on the CORESET. Four different QCL types can be indicated in 3GPP Rel. 15 [4].
One or more of the QCL-Info parameters is/are included in the TCI-state IE to provide the QCL assumption(s) associated with the TCI-state.
For example, a TCI-state IE comprising a DL reference signal ‘A’ with QCL assumption ‘QCL-typeA’ and a DL reference signal ‘B’ with QCL-assumption ‘QCL-TypeD’ is considered. Applying this TCI-state to a PDSCH or CORESET with the given quasi-colocation assumptions means that the UE shall assume the same Doppler shift, Doppler spread, average delay and delay spread for the DMRS ports of the PDSCH or the DMRS ports of the PDCCH(s) transmitted on the CORESET and the DL reference signal A, and the UE shall use the same spatial filter to receive the DL reference signal ‘B’ and the DMRS ports of the PDSCH or the DMRS ports of the PDCCH(s) transmitted on the CORESET.
Usually, the TCI state that is used to schedule a PDCCH or a PDSCH contains the identifiers (IDs) of channel state information reference signals (CSI-RS) or synchronization signal blocks (SSB) along with the QCL assumptions for each reference signal. The RS in the TCI-state is usually a RS that the UE has measured before, so that it can use it as a reference to receive the DMRS of the PDCCH or PDSCH, and hence demodulate the same. The indication of a TCI-state for a CORESET or a PDSCH is performed via MAC Control Element (MAC-CE) messages or using the TCI-indication field in the downlink control information (DCI) used to schedule the PDSCH.
In FR2, where the gNB and UE establish a connection via spatially selective/directive beams, the TCI-state is used to indicate the beam directions in which the UE must receive, i.e., the spatial filter to be used by the UE to receive a PDSCH/PDCCH(s) via a ‘qcl-TypeD’ assumption with a CSI-RS or an SSB that the UE has already received. The determination of the DL Tx beam to transmit PDCCH(s)/PDSCH is performed via a beam sweeping procedure. In a beam sweeping procedure, the gNB configures a set of DL RSs (CSI-RS or SSB) for the UE to measure in the DL via the RRC. Each of the configured DL RS may be transmitted with a different spatial filter, i.e., each of the configured DL RS may be transmitted in a different direction by the gNB. The UE measures each of the configured DL RS by receiving them using one or more spatial filters—the RSs may all be received with the same spatial filter or a different spatial filter may be used to receive each RS. Following the measurements, the UE sends a beam report to the gNB. The beam report comprises the indices of 1≤L≤4 configured DL RSs (essentially, L DL Tx beam directions, with each beam direction resulting from the use of a specific spatial filter at the gNB) along with the received power in each of the RSs [4]. With the help of the beam report, the gNB determines one or more suitable DL Tx beam direction(s), i.e., spatial filter(s) for the transmission of the PDCCH(s) and the PDSCH.
The physical uplink control channel carries control information such as channel state information (CSI) feedback, the hybrid automatic repeat request (HARQ) acknowledgement (ACK)/negative acknowledgements (NACK) for physical downlink shared channel (PDSCH) transmissions, and scheduling requests (SR). A unit of the PUCCH that carries uplink control information (UCI) is a PUCCH resource. A PUCCH resource is an RRC configured space in a certain format (format 0, 1, 2, 3) in a certain UL bandwidth-part (BWP) [3, 6] as shown in
The PUCCH resources that may carry the various types of the uplink control information (UCI)
The beam direction and power control settings of the PUCCH resources are configured together in a ‘PUCCH-SpatialRelationInfo’ IE, as shown in
The derivation of the transmit power of a PUCCH resource comprises the addition of open loop and closed loop power adjustments. If a UE transmits a PUCCH on an active UL bandwidth-part (BWP) b and carrier f in the primary cell c using a PUCCH power control adjustment state with index l, the UE determines the PUCCH transmission power PPUCCH,b,f,c(i, qu, qd, l) in PUCCH transmission occasion i as [3],
where,
The UE is configured up to 8 PUCCH-SpatialRelationInfo parameters in 3GPP Rel. 15.
A specific beam direction and power control setting is applied to a PUCCH resource via a MAC-CE message (as shown in
Sounding reference signals (SRS) are used for sounding the UL channel. The basic unit of the SRS is an SRS resource, which is a specific pattern of reference symbols in time, frequency and code transmitted by all or a subset of UE's antenna ports in the UL to sound the UL channel. The UE is configured by the gNB via RRC with one or more SRS resource sets, with each SRS resource set consisting of one or more SRS resources (shown in
As seen in
The transmit power of SRS is thereby obtained by a combination of parameters configured/indicated to the UE as follows: If a UE transmits SRS on active UL BWP b of carrier f of serving cell c using SRS power control adjustment state with index l, the UE determines the SRS transmission power PSRS,b,f,c(i, qs, l) in SRS transmission occasion i for the SRS resource set qs as
where,
PUSCH transmission(s) can be dynamically scheduled via an UL grant in a PHY-layer downlink control information (DCI) or semi-persistently/statically scheduled with the higher layer configured grant configuredGrantConfig. The configured grant Type 1 PUSCH transmission is semi-statically configured to operate upon the reception of higher layer parameter of configuredGrantConfig including rrc-ConfiguredUplinkGrant without the detection of an UL grant in a DCI. The configured grant Type 2 PUSCH transmission is semi-persistently scheduled by an UL grant in a valid activation DCI [3] after the reception of higher layer parameter configurdGrantConfig not including rrc-ConfiguredUplinkGrant [4].
The physical uplink shared channel can be transmitted in 3 modes: codebook, non-codebook and single-port. The codebook- and non-codebook-based PUSCH transmissions are scheduled using downlink control information (DCI) format 0_1 [4] if the DCI is used in the dynamic or semi-persistent scheduling of the PUSCH. When the PUSCH is scheduled with DCI format 0_0, the UE uses a single port for the PUSCH transmission [4]. The beam direction and power control settings for the PUSCH are differently configured/indicated from that of the PUCCH.
The beam direction of the PUSCH is determined from the beam direction of an SRS or a PUCCH resource depending on the mode of PUSCH transmission:
The power control settings for PUSCH are obtained as follows for the different modes of transmission:
The transmit power of PUSCH is thereby determined from a combination of open loop and closed loop power control parameters. If a UE transmits a PUSCH on active UL BWP b of carrier f of serving cell c using parameter set configuration with index j and PUSCH power control adjustment state with index l, the UE determines the PUSCH transmission power in PUSCH transmission occasion i as
where,
From the above discussion on the UL beam direction and power control framework in 3GPP Rel. 15, issues related to RRC overhead and redundancy have been identified. This overhead in turn leads to higher latency in the update of UL transmission settings which might prove to be a bottleneck when the UE is mobile, for example in FR2 operation.
Some of the specific issues identified in the UL beam direction configuration and indication framework are as follows:
The UL beam direction configuration and indication framework in 3GPP Rel. 15 is illustrated in
The UL beam direction configuration and indication framework in 3GPP Rel. 15 is illustrated in
In addition to the issues in UL beam management discussed above, the inflexibility of the configuration and indication of UL power control settings in 3GPP Rel. 15 is also noteworthy. The pathloss reference RSs used in the derivation of the pathloss factor in the UL Tx power expressions change with respect to UE mobility. In FR2, when the UE moves within the cell, the pathloss reference RS changes with the DL beam used for PDSCH/PDCCH transmissions. Therefore, the list of the pathloss reference RSs configured for the UE and the IEs used to indicate power control settings that refer to the pathloss reference RS IEs have to be constantly reconfigured to keep up with UE mobility, which leads to a lot of control information overhead and latency. However, the power control settings other than the pathloss reference RSs may not change with UE mobility and may be retained by the UE. Therefore, the power settings configuration must be flexible enough to modify only the necessary settings and avoid unnecessary reconfiguration of settings that may stay constant when the UE is mobile. It is therefore necessary to decouple the pathloss reference RSs from the rest of the power control settings and enable implicit updates of the same from the beam(s) of DL channels.
In view of the above drawbacks, it is an objective of the embodiments herein to provide an overhaul of the UL beam configuration and indication framework and the UL power settings framework to reduce control information overhead and latency of UL beam and power settings indication at the UE. It also provides methods to the exploit of the UE's beam correspondence capability to reduce redundant higher layer configurations and use implicit methods for the derivation of UL spatial filter and pathloss reference RSs. The proposed overhaul of the beam management framework may be used along with or separate from the implicit beam direction and pathloss reference RS derivation methods according to some exemplary embodiments of the present invention
According to an aspect of embodiments herein, there is provided a method performed by a UE, the method comprising: receiving, from a network node, via a higher layer, a configuration of an Information element, IE, comprising a set of parameters used for the configuration of an uplink, UL, beam direction or a spatial filter to be used in a UL transmission; wherein the IE contains at least: an ID, unique to each IE and an ID of an UL reference signal, RS resource or a downlink, DL, RS resource; and applying the UL beam direction or spatial filter IE for the transmission of one or more of the Physical Uplink Shared Channel, PUSCH, Physical control channel, PUCCH resource(s) and/or Sounding Reference Signal, SRS resource(s)
According to an aspect of embodiments herein, there is provided a method performed by the UE comprising: receiving, from a network node, a higher layer configuration of at least one downlink reference signal, RS, as a pathloss reference in an, Information Element, IE, containing at least the following parameters: an ID unique for the pathloss reference RS and the ID of a DownLink, DL, Reference Signal, RS; and using said pathloss reference RSs in the configuration of the power control setting(s) and/or in the indication of the pathloss reference for PUCCH resource(s) and either SRS resource(s) or PUSCH or both.
According to another aspect, there is provided a method performed by a UE comprising receiving, from a network node, a higher layer configuration of a grouping/association of Physical Uplink Control Channel, PUCCH, resources:
using CORESET ID values or CORESET group ID values, or by using a PUCCH resource group identifier, PUCCH resource group ID, that is derived from the transmit/receive point (TRP) the PUCCH resources are associated with.
According to another aspect there is provided a method performed by a UE comprising-receiving, from a network node, an Information Element, IE, via a higher layer, of one or more power control settings for a PUCCH, PUCCH-PC-setting, wherein a power control setting contains at least the following parameters: an ID unique for each power control setting IE, a closed loop power control index, a p0-PUCCH-ID and optionally the ID of a pathloss reference RS for PUCCH.
According to another aspect there is provided a UE comprising a processor and a memory, said memory containing instructions executable by said processor whereby the UE is operative to perform any one of the subject-matter of method claims 1-53.
There is also provided a computer program comprising instructions which when executed on at least one processor of the UE claim 54, cause the at least said one processor to carry out the method according to anyone claims 1-53.
A carrier is also provided containing the computer program, wherein the carrier is one of a computer readable storage medium; an electronic signal, optical signal or a radio signal.
Additional embodiments according to other aspects of the present invention are presented in the detailed description.
In the following, a detailed description of the exemplary embodiments is described in conjunction with the drawings, in several scenarios to enable easier understanding of the solution(s) described herein.
In the present embodiments, and as previously described, an overhaul of the UL beam management and power control framework is provided to address the above issues. Methods to configure a common set of beam directions for UL channels and/or RSs, separate from the power control settings are proposed. This is followed by the introduction of methods to implicitly derive beam directions from DL channels/RSs. Methods for the configuration and indication of pathloss reference RSs are further discussed and presented. Implicit methods to derive pathloss reference RS from DL channels are also introduced. The present embodiments further disclose methods to configure PUCCH power control settings and the ways to indicate them.
It is noted that several embodiments are described in the following may be implemented individually or in combination. In other words, some or all of the described embodiments may be combined-unless mutually exclusive.
The configuration and indication framework of the beam directions for PUCCH resources and SRS resources in 3GPP Rel. 15 leads to some redundancies as the same beam direction may be configured more than once for various SRS and PUCCH resources. The combined configuration of power control and beam directions for PUCCH resources makes them usable exclusively for PUCCH resources, and hence when beam directions are configured for SRS resources, the gNB may end up configuring beam directions that have been already configured for PUCCH resources. Moreover, combining the configuration of power control and beam direction is inefficient in addressing the different needs of beam direction indication for UEs with and without beam correspondence capability. Such higher layer configuration leads to large RRC overhead and latency.
An illustration of a framework that can address the RRC redundancy/overhead in beam direction indication is shown in
According to an embodiment there is provided a method performed by a UE comprises: receiving from a, from a network node, via a higher layer, a configuration of an Information element (IE), comprising a set of parameters used for the configuration of an UL beam direction or a spatial filter to be used in a UL transmission; wherein the IE contains at least: an identifier, ID, unique to each IE and an ID of an UL RS resource or a DL, RS resource; and applying the UL beam direction or spatial filter IE for the transmission of one or more of the Physical Uplink Shared Channel, PUSCH, Physical control channel, PUCCH resource(s) and/or Sounding Reference Signal, SRS resource(s).
In detail, the UE may be configured to receive from the gNB or any other network entity, the IE via a higher layer (e.g., RRC) comprising a set of parameters used for the configuration of an UL beam direction. For example, the IE may be titled as ‘UL-SpatialFilter’. The ‘UL-SpatialFilter’ IE contains at least the following parameters: an identifier (ID) unique to each ‘UL-SpatialFilter’ IE and an identifier (ID) of an UL or a DL resource. The ID of the UL or DL resource is used to indicate an UL beam direction (spatial filter) for one or more PUCCH resources(s) and/or PUSCH and/or one or more SRS resource(s) in an UL transmission. The ID of the DL or UL resource comprises at least one of the following: a CSI-RS resource, an SRS resource or a synchronization signal block (SSB). An example configuration of the ‘UL-SpatialFilter’ IE is shown in
In the case that the resource used to indicate the beam direction in the ‘UL-SpatialFilter’ IE is an SRS resource (an UL resource), the ID of the SRS resource and the ID of the uplink bandwidth part (BWP)—the part of UL frequency band-on which the SRS is transmitted may additionally be included. Note that there are multiple UL BWPs configured, but only one active UL BWP is used for the UL transmission. The UL BWP ID is included in the IE for the case that the SRS resource was transmitted in a previously active UL BWP. The spatial filter used to transmit the SRS resource in the UL BWP indicated in the ‘UL-SpatialFilter’ IE is then used for one or more SRS or PUCCH resource(s) in an UL transmission. The serving cell ID contained in the ‘UL-SpatialFilter’ IE indicates the associated cell.
The UE may be configured with B≥1 ‘UL-SpatialFilter’ IEs and the network node or base station or any other network entity may indicate a specific ‘UL-SpatialFilter’ IE (i.e., UL beam direction) for one or more SRS and/or PUCCH resources via a MAC-CE message.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a MAC-CE message that contains at least an ID of one or more PUCCH resource(s) or SRS resource(s) and the ID of a ‘UL-SpatialFilter’ IE. The UE may apply the spatial filter IE for the transmission of the UL RS resource, or the reception of the DL RS resource configured in the indicated UL beam direction or spatial filter IE for the transmission of indicated PUCCH resource(s) or SRS (resource(s)).
When the UE is configured with B≥1 ‘UL-SpatialFilter’ IEs, the ID of the ‘UL-SpatialFilter’ IE used in the MAC-CE message may be indicated via a bitmap of length B. Each bit in the bitmap is associated with one of the configured ‘UL-SpatialFilter’ IEs. The bitmap then contains a single ‘1’ indicating the ‘UL-SpatialFilter’ IE to be applied.
When the UE receives the MAC-CE message, the UE applies the indicated ‘UL-SpatialFilter’ IE to the indicated PUCCH resource(s) or SRS resource(s) (examples of the MAC-CE are shown in
Similarly, the beam direction for a PUSCH can be indicated to the UE via the PDCCH that schedules the PUSCH or a higher layer configured UL grant for the PUSCH.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, an x-bit field in the PDCCH that schedules a PUSCH, wherein the x-bit field indicates a ‘UL-SpatialFilter’ IE. The field may be named, UL-SpatialFilter indicator, for example. When the UE receives the said PDCCH, the UE applies the ‘UL-SpatialFilter’ IE indicated by the UL-SpatialFilter indicator field in the PDCCH to the PUSCH scheduled by the PDCCH.
In accordance with embodiments, the UE is configured to receive from the gNB or any other network entity, a higher layer configuration of an UL grant that comprises the ID of a ‘UL-SpatialFilter’ IE. When the UE receives the higher layer configuration, the UE applies the ‘UL-SpatialFilter’ IE to the PUSCH scheduled by the UL grant.
The application of a UL-SpatialFilter to a PUCCH resource or an SRS resource or a PUSCH results in the following UE behaviour:
In
The example MAC-CE messages shown in
Example 1 shows a MAC-CE message that contains a bitmap to indicate the UL-SpatialFilter IE. Example 2 shows a MAC-CE message that contains the ID of the UL-SpatialFilter IE to be applied
The ‘UL-SpatialFilter’ IE is used to explicitly indicate the beam direction for PUCCH resources, SRS resources and/or PUSCH, especially in FR2. However, such an explicit indication may not be required for UEs supporting beam correspondence. When a UE supports beam correspondence, the UL beam may be derived implicitly from DL channels thereby eliminating the need for explicit indication of the UL beam direction using a DL RS whenever there is a change in the UL beam direction. The implicit UL beam indication is especially helpful when the UE moves within a cell resulting in frequent beam direction changes. The following embodiments provide a method to implicitly derive the UL beam direction from a CORESET so that frequent explicit beam direction indications may be avoided.
In accordance with embodiments, the UE is configured to receive from the gNB or any other network entity a ‘UL-SpatialFilter’ IE via a higher layer, wherein the ‘UL-SpatialFilter’ IE comprises a CORESET ID. The CORESET ID in the UL-SpatialFilter IE indicates that the UE may use the same spatial filter for the reception of the PDCCH(s), transmitted on the said CORESET, and the transmission of one or more PUCCH resource(s) and/or SRS resource(s) and/or PUSCH in an UL transmission. An example configuration of a ‘UL-SpatialFilter’ IE with a CORESET ID (denoted as ‘controlResourceSetld’) is shown in
When the UE receives a MAC-CE message indicating an UL-SpatialFilter IE containing a CORESET ID and the ID(s) of one or more PUCCH/SRS resource(s), the UE applies the indicated ‘UL-SpatialFilter’ IE to the indicated PUCCH/SRS resource(s).
Similarly, when the UE receives a PDCCH scheduling a PUSCH with a field indicating a ‘UL-SpatialFilter’ IE containing a CORESET ID or a higher layer configured UL grant scheduling a PUSCH comprising the ID of a ‘UL-SpatialFilter’ IE containing a CORESET ID, the UE applies the indicated ‘UL-SpatialFilter’ IE to the PUSCH scheduled by the PDCCH or the higher layer configured UL grant respectively.
The application of a UL-SpatialFilter containing a CORESET ID to a PUCCH resource or an SRS resource or a PUSCH results in the following UE behaviour:
This means, at every instance the spatial filter used for the reception of the PDCCH(s) in a CORESET is changed due to a TCI-state update for the CORESET, the UE also updates the spatial filter used for the transmission of the SRS and/or PUCCH resource(s) to the same spatial filter used for the reception of the PDCCH(s) transmitted on the CORESET. In UE mobility scenarios, this leads to a high reduction in control information signaling.
This method of beam indication may be especially helpful in the case of PUCCH resource(s) carrying ACK/NACKs of PDSCH transmission(s). The UL beam direction of the PUCCH resources may follow the DL beam direction used for the CORESET on which the PDCCH(s) indicating the PUCCH resource(s) are transmitted. Hence, whenever there is a change of the DL beam direction for the PDCCH(s) transmitted on the CORESET, the UL beam direction of the PUCCH resource(s) may change accordingly. In a multi-TRP (transmit/receive point) transmission scenario, where each CORESET may be associated with a particular TRP, this method of beam indication helps to direct the HARQ ACK(s)/NACK(s) for the PDSCH transmitted from a TRP to the same TRP with much less control overhead and latency, even when a UE is mobile and moving within the cell.
A message flow chart showing the timeline of a beam indication with the help of a CORESET ID is provided in
MAC-CE messages may be used to indicate the UL beam direction for either a single PUCCH resource, or multiple, i.e., a group of PUCCH resources. The MAC-CE indication for a group of PUCCH resources may enable the gNB to update properties for groups of PUCCH resources, thereby reducing the signaling overhead. Such properties may include an UL beam direction, a power control setting, or a HARQ codebook. The indication of these properties for a group of PUCCH resources may be aided using a higher layer configured grouping method. In the following, various grouping schemes for PUCCH resources are discussed and associated MAC-CE message indications are introduced.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a higher layer configuration of a grouping/association of PUCCH resources using CORESET ID values or CORESET group ID values. The CORESETs configured for a UE may be grouped via higher layer configuration, for example, according to the transmit/receive point (TRP) they are associated with. In a multi-TRP transmission scenario, a CORESET is associated with a TRP. The set of CORESETs that are associated with a TRP may be grouped with a common CORESET group ID via higher layer configuration. The PUCCH resources associated with a specific CORESET ID/CORESET group ID value via higher layer configuration form a PUCCH resource group. When grouped in connection with a CORESET or a CORESET group in the DL, the properties of the PUCCH resources such as beam direction, power control settings and HARQ codebook can be modified in connection with the CORESET or the CORESET group they are associated with, especially for UEs with beam correspondence.
An example of associating a PUCCH resource IE with a CORESET via PUCCH resource IE configuration is provided in
In accordance with an embodiment, the UE is configured to receive, from the gNB or any other network entity, a higher layer configuration of a grouping/association of PUCCH resources using an ID that may be derived from the transmit/receive point (TRP) the PUCCH resources are associated with. The ID may be called ‘PUCCH Resource Group ID’, for example. The grouping with respect to TRPs may be performed in multi-TRP scenarios when the uplink control information (UCI) specific to a TRP such as CSI feedback and HARQ ACK(s)/NACK(s) for PDSCHs transmitted from a TRP, may be transmitted to the same TRP. With this method of grouping, the properties of PUCCH resources may be modified independent of the DL resources/channels such as CORESETs or PDSCHs. It may be especially helpful in the following scenarios:
Considering the PUCCH resource grouping techniques described above, MAC-CE messages can be used to indicate the beam direction for a group of PUCCH resources.
In accordance with an embodiment, the UE is configured to receive from the gNB, a MAC-CE message that contains at least the following: a serving cell ID, a CORESET ID or a CORESET group ID, an ‘UL-SpatialFilter’ ID and optionally, an UL BWP ID. When the UE receives the MAC-CE message without the UL BWP ID, the UE applies the UL-SpatialFilter to the PUCCH resources configured with the indicated CORESET ID or CORESET group ID or to any PUCCH resource(s) indicated via the PUCCH resource indicator field by the PDCCH(s) transmitted on the indicated CORESET or on the CORESET(s) belonging to the indicated CORESET group. The serving cell ID indicates the cell the MAC-CE message is intended for. If the MAC-CE is received with an UL BWP ID, the UL-SpatialFilter is applied to the said PUCCH resources configured only within the indicated UL BWP.
In accordance with an embodiment, the UE is configured to receive from the gNB, a MAC-CE message that contains at least the following: a serving cell ID, a PUCCH resource group ID, an ‘UL-SpatialFilter’ ID and optionally, an UL BWP ID. When the UE receives the MAC-CE, the UE applies the UL-SpatialFilter to the PUCCH resources configured with the indicated PUCCH resource group ID. If the MAC-CE is received with an UL BWP ID, the UL-SpatialFilter is applied to the said PUCCH resources configured only within the indicated UL BWP.
For UEs satisfying beam correspondence, methods for implicit beam indication for PUCCH resources that follow the DL beam direction used for a CORESET are provided above. The implicit indication is enabled via a MAC-CE message indicating an ‘UL-SpatialFilter’ IE comprising a CORESET ID or CORESET group ID. In the following, alternative methods for implicit beam indication/beam determination for PUCCH resources via a higher layer configuration are provided, that help in faster beam indication/switch and thereby, reduced control information overhead.
In accordance with an embodiment, if the PUCCH resources are grouped explicitly via a higher layer configuration using CORESET ID values, the UE is configured to use the same spatial filter for the transmission of a group of PUCCH resources associated with a CORESET via higher layer configuration as for the reception of the PDCCH(s) on the CORESET. For example, if a group of PUCCH resources are associated with a CORESET c; via higher layer configuration, the UE uses the same spatial filter for the transmission of the group of PUCCH resources as for the reception of the PDCCH(s) on the CORESET ci.
In accordance with an embodiment, if the PUCCH resources are grouped explicitly via a higher layer configuration using CORESET group ID values, the UE is configured to use the same spatial filter for the transmission of a group of PUCCH resources associated with a CORESET group via higher layer configuration as for the reception of the PDCCH(s) on one of the CORESETs in the CORESET group. For example, if a group of PUCCH resources are associated with the CORESET group gi via higher layer configuration and CORESETS ci1 and ci2 belong to the CORESET group gi, the UE uses the same spatial filter for the transmission of the group of PUCCH resources as for the reception of the PDCCH(s) on either the CORESET ci1 or CORESET ci2. In certain cases, there may be a default CORESET assumption for each CORESET group that the UE may use as a reference for the spatial filter to be used for the transmission of the PUCCH resources grouped with the said CORESET group ID value. For example, the CORESET with the lowest/highest CORESET ID value in the CORESET group may be taken as the default CORESET for spatial filter reference.
The above UE behavior may be enabled via a higher layer parameter so that in the case of UEs with beam correspondence, if the parameter is enabled, the UE derives the spatial filter for the group of PUCCH resources from the appropriate CORESET(s).
In accordance with an embodiment, the UE is configured by the gNB or any other network entity with a higher layer parameter that indicates whether the UE may use the same spatial filter as for the reception of the PDCCH(s) on a CORESET for the transmission of a group of PUCCH resources associated via higher layer configuration with the same CORESET or the same CORESET group as the one the CORESET belongs to.
Apart from the grouping strategies mentioned above, a dynamic update of the properties of UL resources without grouping is also possible as well, especially with PUCCH resources carrying HARQ ACK/NACK. According to the CORESET on which the PDCCH indicating the PUCCH resource to carry the HARQ ACK/NACK is transmitted, the beam directions can be implicitly indicated for PUCCH resources from the CORESET.
The PUCCH resources on which the ACK(s)/NACK(s) for PDSCH(s) are to be transmitted are indicated in the PDCCH scheduling the PDSCH. For UEs satisfying beam correspondence, the beam direction of the PUCCH resources, carrying HARQ ACK(s)/NACK(s), may follow the beam direction of the CORESET on which the PDCCH(s) indicating them are transmitted. Such UE behavior may be specified as default when the PUCCH resources are not indicated with a spatial filter/PUCCH spatial relation to be used. This UE behavior can also be facilitated with the help of a higher layer parameter which indicates if the PUCCH resources follow the beam direction used for the reception of the PDCCH(s) indicating them.
In accordance with an embodiment, the UE is configured to use the same spatial filter used for the reception of the PDCCH(s) on a CORESET for the transmission of PUCCH resource(s) indicated in the PUCCH resource indicator field of the PDCCH(s) transmitted on the CORESET.
In accordance with an embodiment, the UE is configured to use the same spatial filter used for the reception of the PDCCH(s) on a CORESET for the transmission of the PUCCH resource(s) indicated in the PUCCH resource indicator field of the PDCCH(s) transmitted on the CORESET when the PUCCH resource(s) is (are) not configured/indicated with a spatial filter.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a higher layer parameter that indicates whether the spatial filter used by the UE for the reception of the PDCCH(s) on a CORESET may be used for the transmission of the PUCCH resource(s) indicated in the PUCCH resource indicator field of the PDCCH(s) transmitted on the CORESET.
As example, the higher layer parameter may be titled as an ‘pucchSpatialFilterFollowsCORESET’ and may take the value ‘enabled’ or ‘disabled’. If the parameter ‘pucchSpatialFilterFollowsCORESET’ is set to ‘enabled’, the UE uses the same spatial filter used for the reception of the PDCCH(s) on the CORESET and the transmission of the PUCCH resources indicated by the PUCCH resource indicator field in the PDCCH(s) transmitted on the CORESET.
The beam direction for a PUCCH resource, in this method, is dynamically determined without the necessity of indicating the beam direction for each PUCCH resource, or a group of PUCCH resources via a MAC-CE message or an explicit grouping of PUCCH resources via a higher layer configuration.
The beam direction of PUCCH resources carrying HARQ ACK(s)/NACK(s) may also be enabled to implicitly follow the PDSCH for which they carry the ACK(s)/NACK(s). The beam direction of the PDSCH is indicated via a TCI state, and it may follow the beam direction of the CORESET on which the PDCCH scheduling the PDSCH is transmitted. Alternatively, the beam direction may be indicated by the PDCCH scheduling the PDSCH in a 3-bit TCI-state indication field. This UE behavior may be enabled as default when no spatial filter/spatial relation is indicated for a PUCCH resource or it can be enabled via a higher layer parameter.
In accordance with an embodiment, the UE is configured to use the same spatial filter used for the reception of a PDSCH for the transmission of the PUCCH resource(s) that carry the HARQ ACK/NACK for the PDSCH.
In accordance with an embodiment, the UE is configured to use the same spatial filter used for the reception of a PDSCH for the transmission of the PUCCH resource(s) that carry the HARQ ACK/NACK for the PDSCH, when the PUCCH resource(s) is (are) not configured/indicated with a spatial filter.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a higher layer parameter, that indicates whether the spatial filter used by the UE for the reception of a PDSCH may be used for the transmission of the PUCCH resource(s) that carry the HARQ ACK/NACK for the PDSCH. As an example, the parameter may be titled ‘pucchSpatialFilterFollowsPDSCH’, and may take the value ‘enabled’ or ‘disabled’. If the parameter ‘pucchSpatialFilterFollowsPDSCH’ is set to enabled, the UE uses the same spatial filter for the transmission of the PUCCH resource(s) carrying the HARQ ACK(s)/NACK(s) for a PDSCH as for the reception of the PDSCH.
In this section, methods for configuration and indication of the power control settings for various UL channels/RSs in a way to reduce higher layer overhead and latency from the state of the art are introduced in accordance with some embodiments herein. The pathloss reference RSs, specifically, are discussed in detail. The redundancy in the configuration of the pathloss reference RSs is discussed first, followed by the introduction of methods to indicate the same via MAC-CE messages and PHY-layer signaling.
Each PUSCH/PUCCH/SRS pathloss reference RS IE/parameter in 3GPP Rel. 15 comprises a DL RS to be used as a pathloss reference. When a PUCCH/SRS resource or PUSCH is configured/indicated with a pathloss reference RS IE/parameter, the UE uses the DL RS indicated as the pathloss reference to derive the pathloss factor/estimate for the calculation of the transmit power of the said PUCCH/SRS resource or PUSCH. The pathloss reference RSs, are configured separately for PUCCH, SRS and PUSCH in 3GPP Rel. 15. Such a separate configuration results in a large signaling overhead since the same pathloss reference RS is configured for different UL channels and UL resources. Moreover, as the maximum number of pathloss reference RSs that can be configured for both PUSCH and PUCCH in 3GPP Rel. 15 is restricted as part of the UE's capability [6], frequent RRC reconfiguration of the pathloss reference RSs is performed when a UE moves within a cell. A common configuration of the pathloss reference RSs for PUCCH, and either SRS or PUSCH or both that avoids reconfigurations for each UL channel/RS is introduced in the following.
In accordance with embodiments, the UE is configured to receive, from the gNB or any other network entity, a higher layer configuration of a pathloss reference RS IE containing at least the following parameters: an ID unique for the pathloss reference RS and the ID of a DL RS, e.g., a CSI-RS resource or an SSB. The UE may use the IDs of the configured pathloss reference RS IEs in the IEs used to configure the power control settings for PUCCH and, either SRS or PUSCH or both. When PUSCH/SRS resource(s)/PUCCH resource(s) is (are) configured/indicated with power control settings containing the ID of a pathloss reference RS IE, the UE uses the DL RS configured in the said pathloss reference RS IE to derive the pathloss factor for the calculation of the transmit power for the UL transmission(s) of the said PUSCH/SRS resource(s)/PUCCH resource(s). The pathloss factor of subcarrier f in serving cell c is computed from the indicated pathloss reference RS qd as PLf,c(qd)=ReferenceSignalPower-RSRP, where RSRP is the higher layer filtered reference signal received power and where the ReferenceSignalPower is the transmit power of the pathloss reference RS provided by higher layers and the RSRP is computed by the physical layer and filtered by higher layers. The higher layer filter may be designed as described in [6].
Having a common pathloss reference RS configuration for PUCCH, PUSCH and SRS instead of independent configurations for each of them also reduces the redundancy in RRC configuration. The UE may receive up to P≥1 pathloss reference RS configurations. An example configuration of the pathloss reference RS IE is provided in
An illustration of how the pathloss reference RSs are configured in 3GPP Rel. 15 and how a version of the proposed common pathloss reference RS configuration may be implemented are shown in
The common configuration of the pathloss reference RSs addresses the redundancy in configuration of the pathloss reference RSs. However, when the list of pathloss reference RSs for the UE is reconfigured (for e.g., when the UE is moving in the cell and the gNB allocates a new set of beams for the UE to indicate pathloss reference(s)), the IEs that include the pathloss reference RSs such as ‘SRI-PUSCH-PowerControl’, ‘PUCCH-SpatialRelationInfo’, etc. would also need to be reconfigured. Therefore, to avoid reconfiguring all concerned IEs, the pathloss reference RSs may be updated for the required PUCCH/SRS resource and/or PUSCH via MAC-CE or PHY-signaling, thereby reducing the control overhead. The following embodiments describe signaling schemes for updating the introduced pathloss reference RSs for PUSCH, SRS and PUCCH via MAC-CE and PHY-layer messages.
In accordance with an embodiment, the UE is configured to receive a MAC-CE message from the gNB or any other network entity that contains at least a pathloss reference RS ID and the ID(s) of one or more SRS resource(s) or SRS resource set(s). When the UE receives the MAC-CE message, the UE uses the RS configured in the indicated pathloss reference RS IE to derive the pathloss factor for the calculation of the transmit power for the UL transmission of the indicated SRS resource(s) or all the SRS resources configured in the indicated SRS resource set(s).
The update of the pathloss reference RSs using MAC-CE messages for PUCCH may be performed with the pathloss reference RS configuration proposed above or with the existing 3GPP Rel. 15 configuration of the pathloss reference RSs for PUCCH-‘PUCCH-PathlossReferenceRS’.
In accordance with an embodiment, the UE is configured to receive a MAC-CE message from the gNB or any other network entity that contains at least a pathloss reference RS ID or the ID of at least one ‘PUCCH-PathlossReferenceRS’ according to 3GPP Rel. 15, and the ID(s) of one or more PUCCH resources. When the UE receives the MAC-CE message, the UE uses the DL RS configured in the indicated pathloss reference RS IE to derive the pathloss factor for the calculation of the transmit power for the UL transmission(s) of the indicated PUCCH resource(s).
The PUCCH resource grouping methods may be used to indicate the pathloss reference RS to be used for the transmission of a group of PUCCH resources.
In accordance with embodiments, the UE is configured to receive a MAC-CE message from the gNB or any other network entity that contains at least a pathloss reference RS ID or the ID of at least one ‘PUCCH-PathlossReferenceRS’ according to 3GPP Rel. 15, and a CORESET ID, or a CORESET group ID, or a PUCCH resource group ID. When the UE receives the MAC-CE message, the UE uses the RS configured in the indicated pathloss reference RS configuration to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the group of PUCCH resource(s) associated with the indicated CORESET ID/CORESET group ID/PUCCH resource group ID via higher layer configuration or to any PUCCH resource(s) indicated via the PUCCH resource indicator field by PDCCH(s) transmitted on the indicated CORESET or on the CORESET(s) belonging to the indicated CORESET group.
The MAC-CE messages described may contain a serving cell ID to indicate the serving cell the MAC-CE message applies to. The messages may also be used to update the pathloss reference RS of PUCCH/SRS resources only in a specific UL-BWP. In certain cases, the UE may require that it update the pathloss reference RSs for PUCCH/SRS only within the active BWP or a BWP it might switch to and not for all the PUCCH/SRS in the whole cell. The inclusion of the UL-BWP provides the option to update the pathloss reference RS for only a subset of the PUCCH resources in the cell.
In accordance with an embodiment, the MAC-CE message received by the UE from a gNB or any other network entity to update the pathloss reference RS for a PUSCH, or one or more or a group of PUCCH/SRS resources, may contain an UL BWP ID and a serving cell ID. If the UE receives the MAC-CE message with an UL-BWP ID, the UE uses the RS configured in the indicated pathloss reference RS configuration to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the said PUSCH or PUCCH/SRS resources in the indicated UL BWP of the indicated serving cell.
In addition to the MAC-CE-based indication of the pathloss reference RS, a physical layer indication of the same via a PDCCH can be performed for PUCCH and/or PUSCH.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a PDCCH containing a pathloss reference RS indicator field, whose value maps to one of the higher-layer-configured pathloss reference RS IEs or at least one higher layer configured ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Rel. 15. When the UE receives the PDCCH, it uses the RS configured in the indicated pathloss reference RS IE to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource indicated by the PUCCH resource indicator field in the PDCCH or the PUSCH scheduled by the PDCCH.
When the PUSCH is scheduled by a PDCCH with DCI format 0_1, the higher layer parameter SRI-PUSCH-PowerControl provides the power control settings for the PUSCH transmission [4, 6]. The sounding reference signal indicator (SRI) in the DCI that indicates the ports of the SRS resource that need to be used to transmit the PUSCH, maps to one of the power control parameters, i.e., ‘SRI-PUSCH-PowerControl’ IEs, that contains the pathloss reference RS as well. In the case of mobility, if the pathloss reference RS has to be modified, RRC reconfiguration of the ‘SRI-PUSCH-PowerControl’ parameters would be required that increases latency of the pathloss RS update.
In the following, methods for MAC-CE-based pathloss reference RS update for PUSCH that would support higher mobility are introduced. And the MAC-CE messages may use the pathloss reference RSs that are configured as described above or use the PUSCH pathloss reference RS configuration in 3GPP Rel. 15.
In accordance with embodiments, the UE is configured to receive a MAC-CE message from the gNB or any other network entity to update the pathloss reference RS of a PUSCH. The MAC-CE message contains at least a pathloss reference RS ID or at least one ‘PUSCH-PathlossReferenceRS’ ID according to 3GPP Rel. 15, and a UL BWP ID. When the UE receives the MAC-CE message, the UE uses the RS configured in the indicated pathloss reference RS configuration to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUSCH in the indicated UL BWP.
In accordance with embodiments, the UE is configured to receive a MAC-CE message from the gNB or any other network entity that contains at least a pathloss reference RS ID or at least one ‘PUSCH-PathlossReferenceRS’ ID according to 3GPP Rel. 15, and an SRI-PUSCH-PowerControl ID. When the UE receives the MAC-CE message, the UE updates the pathloss reference RS to be used with the indicated ‘SRI-PUSCH-PowerControl’ IE with the pathloss reference RS indicated in the MAC-CE message.
In accordance with embodiments, the UE is configured to receive a MAC-CE message from the gNB or any other network entity that contains at least a pathloss reference RS ID or at least one ‘PUSCH-PathlossReferenceRS’ ID according to 3GPP Rel. 15, and the value of a sounding reference signal index/indicator (SRI). When the UE receives the MAC-CE message, the UE uses the RS configured in the indicated pathloss reference RS configuration to derive the pathloss factor for the calculation of the transmit power for an UL transmission of a PUSCH scheduled with the indicated SRI value via the PDCCH or a configured UL grant.
Explicit configuration and indication of the pathloss reference RSs is usually performed in 3GPP Rel. 15 when the UE operates at frequency range 2 (FR2). For PUCCH, the pathloss reference RSs are configured and included in ‘PUCCH-SpatialRelationInfo’ IEs. A specific ‘PUCCH-SpatialRelationInfo’ IE is indicated for each PUCCH resource via a MAC-CE message. In case of the SRS, the pathloss reference RS is explicitly configured per SRS resource set when the UE operates at FR2. For PUSCH, a list of pathloss reference RSs are configured via a higher layer and included in ‘SRI-PUSCH-PowerControl’ IEs. When a PUSCH is scheduled, a mapping from the SRI used to schedule the PUSCH to the ‘SRI-PUSCH-PowerControl’ IEs determines the pathloss reference RS.
When the UE is moving within a cell, the DL beam used to receive a DL channel may change frequently. This may lead to permanent higher layer re-configurations of the pathloss reference RSs used to derive the UL transmission power. Such frequent re-configurations increase the signaling overhead and reduce the overall network efficiency.
The following embodiments provide schemes for implicit indication of the pathloss reference RS which are based on the TCI-state indication of a DL channel by the gNB. Such implicit indication avoids the frequent re-configuration and explicit indication of the pathloss reference using DL RSs when the UE is moving within a cell thereby reducing signaling overhead and latency of pathloss reference RS indication.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a higher layer configuration of a pathloss reference RS IE or a PUCCH/PUSCH/SRS pathloss reference RS IE/parameter according to 3GPP Rel. 15 comprising a CORESET ID. An example configuration of the pathloss reference RS IE containing a CORESET ID is shown in
When the UE receives a MAC-CE message indicating a pathloss reference RS configuration containing a CORESET ID for one or more PUCCH/SRS resource(s) or PUSCH, the UE uses the DL RS configured with ‘qcl-TypeD’ in the TCI-state of the CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the said PUCCH/SRS resource(s) or PUSCH. At every instance the TCI-state for the CORESET is updated, the UE also updates the pathloss reference RS of the said PUCCH/SRS resources or PUSCH with the DL RS configured with ‘qcl-TypeD’ in the TCI-state of the CORESET. This implicit indication of the pathloss reference RS allows the UE to follow the DL Rx beam for pathloss reference thereby eliminating the explicit signaling of the same whenever there is a change in the DL beam.
The implicit derivation of the pathloss reference RS may be performed for PUCCH resources carrying the HARQ ACK(s)/NACK(s) from the CORESET on which the PDCCH(s) indicating them are transmitted. This implicit derivation may be performed by the UE when the UE is configured via a higher layer indication or when there is no configuration/indication of a pathloss reference RS for the PUCCH resource.
In accordance with an embodiment, the UE is configured to use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource(s) indicated by the PUCCH resource indicator field in the PDCCH(s) transmitted on the CORESET.
In accordance with an embodiment, the UE is configured to use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource(s) indicated by the PUCCH resource indicator field in the PDCCH(s) transmitted on the CORESET, when there is no configuration/indication of pathloss reference RS(s) of the PUCCH resource(s).
In accordance with an embodiment, the UE is configured to receive, from the gNB or any other network entity, a higher layer parameter to indicate whether the UE may use the DL RS, configured with ‘qcl-TypeD’, in the TCI-state of a CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resources indicated by the PUCCH resource indicator field in the PDCCH(s) transmitted on the CORESET. The parameter may be titled ‘PUCCHPLRefRSfromCORESET’, for example, and its possible values may be ‘enabled’ and ‘disabled’. When the parameter is set to ‘enabled’, the UE uses the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resources indicated by the PUCCH resource indicator field in the PDCCH(s) transmitted on the CORESET.
A similar scheme may be applied in the case of PDSCH to enable to PUCCH resource carrying the HARQ ACK/NACK for the PDSCH to derive the pathloss reference RS from the TCI-state of the PDSCH.
In accordance with an embodiment, the UE is configured to use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a PDSCH to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource(s) that carries the HARQ ACK(s)/NACK(s) for the PDSCH.
In accordance with an embodiment, the UE is configured to use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a PDSCH to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource(s) that carries the HARQ ACK(s)/NACK(s) for the PDSCH, when there is no configuration/indication of pathloss reference RS(s) of the PUCCH resource(s).
In accordance with an embodiment, the UE is configured to receive, from the gNB or any other network entity, a higher layer parameter to indicate whether the UE shall use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a PDSCH to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource that carries the HARQ ACK(s)/NACK(s) for the PDSCH. The parameter may be titled ‘PUCCHPLReferenceRSfromPDSCH’, for example, and its possible values may be ‘enabled’ and ‘disabled’. When the parameter is set to ‘enabled’, the UE uses the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a PDSCH to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource that carries the HARQ ACK(s)/NACK(s) for the PDSCH.
Implicit pathloss reference RS derivation may also be performed in the case of PUCCH resources that have been explicitly grouped using a CORESET ID or a CORESET group ID.
In accordance with an embodiment, the UE is configured to use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of a group of PUCCH resources associated with the CORESET via higher layer configuration.
In accordance with an embodiment, the UE is configured to use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of one of the CORESETs in a CORESET group to derive the pathloss factor for the calculation of the transmit power for an UL transmission of a group of PUCCH resources associated with the CORESET group via higher layer configuration. For example, a default CORESET such as the CORESET with the lowest/highest CORESET ID in a CORESET group may be assumed for the choice of pathloss reference RS source.
In accordance with an embodiment, the UE is configured by the gNB or any other network entity to receive a higher layer parameter to indicate whether the UE shall use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET as the pathloss reference RS of a group of PUCCH resources associated with the CORESET or associated with the same CORESET group as the CORESET via higher layer configuration. The parameter may be titled ‘pucchGroupingPLRefRSAssumption’, for example, and may take values ‘enabled’ and ‘disabled’. When the parameter is set to ‘enabled’, the UE uses the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET as the pathloss reference RS of a group of PUCCH resources associated with the CORESET or associated with the same CORESET group as the CORESET via higher layer configuration.
In 3GPP Rel. 15, the power control settings for PUCCH resources are configured along with the UL beam direction RS in ‘PUCCH-SpatialRelationInfo’. As mentioned before, combining the configuration of power control and beam directions is inefficient in addressing the different needs of beam direction indication for UEs with differing beam correspondence capabilities. Moreover, decoupling of the power control parameters that may not change with UE mobility from the ones that change helps in reducing unnecessary RRC signaling. In the following embodiments, methods to configure power control settings separate from the beam direction settings and methods to decouple pathloss reference RSs from the rest of the power control settings are provided.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, an information element via a higher layer of one or more power control settings for the PUCCH, wherein a power control setting contains at least the following parameters: an ID unique for each power control setting IE, a closed loop power control index, a p0-PUCCH-ID and optionally the ID of a pathloss reference RS. The parameter might be titled as ‘PUCCH-PC-setting’, for example, (PC stands for Power Control). An example configuration of the IE is shown in
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a MAC-CE message containing at least the following parameters: a ‘PUCCH-PC-setting’ ID and one or more PUCCH resource IDs. When the UE receives the said MAC-CE message, the UE applies the power control settings indicated by the PUCCH-PC-setting to the PUCCH resource(s) indicated in the MAC-CE message, i.e., the UE uses the power control settings indicated in the MAC-CE message, to derive the transmit power for the said PUCCH resources in an UL transmission.
The transmission power may be derived using the power control parameters in the ‘PUCCH-PC-setting’ with the formula for PPUCCH provided in [3].
In another alternative, since the pathloss reference RSs change due to UE mobility, the indication of the pathloss reference RSs can be performed via MAC-CE messages. The MAC-CE used to update the pathloss reference RS for PUCCH may indicate one of the pathloss reference RS IEs introduced above or one of the PUCCH pathloss reference RS IEs configured according to 3GPP Rel. 15.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a MAC-CE message containing at least the following parameters: a ‘PUCCH-PC-setting’ ID, a pathloss reference RS ID or at least one ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Rel. 15, and one or more PUCCH resource IDs. When the UE receives the MAC-CE message, the UE uses the power control settings in the PUCCH-PC-setting and the indicated pathloss reference RS to derive the transmission power of the said PUCCH resources. If the ‘PUCCH-PC-setting’ indicated in the MAC-CE message is configured with a pathloss reference RS, the UE replaces the same with the pathloss reference RS indicated in the MAC-CE message.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a MAC-CE message containing at least the following parameters: a ‘PUCCH-PC-setting’ ID, one or more PUCCH resource IDs, a UL-SpatialFilter ID, and optionally, a pathloss reference RS ID. When the UE receives the MAC-CE message with a pathloss reference RS ID or the PUCCH reference RS ID according to 3GPP Rel. 15, the UE applies the indicated UL-SpatialFilter to the indicated PUCCH resources and the power control settings in the indicated PUCCH-PC-setting and the indicated pathloss reference RS are used to derive the transmit power for the indicated PUCCH resources. If the ‘PUCCH-PC-setting’ indicated in the MAC-CE message is configured with a pathloss reference RS, the UE replaces the same with the pathloss RS indicated in the MAC-CE message. When the UE receives the MAC-CE message without the pathloss reference RS ID, the UE applies the indicated UL-SpatialFilter and the power control settings indicated in ‘PUCCH-PC-setting’ to the indicated PUCCH resources, and the pathloss reference RS for the indicated PUCCH resources is obtained from one of the following by the UE:
With a decoupled indication of the pathloss reference RSs and the ‘PUCCH-PC-setting’ IEs that contain the power control settings that may remain constant as the UE moves within the cell, the control information overhead is reduced. The updates of parameters that remain unchanged with UE mobility need not be reconfigured as a consequence. Moreover, a flexible MAC-CE-based update of multiple higher-layer-configured PUCCH transmission settings (pathloss reference RS, PUCCH-PC-settings, spatial filter) is introduced. This leads to lower latency in the update of the transmission settings for the said PUCCH resources.
Update of power control, pathloss reference and/or spatial filter for a group of PUCCH resources
The methods used to group PUCCH resources via higher layer configuration may be exploited to update their power control settings as described above. In the following, various methods for the update of the power control settings for a group of PUCCH resources via MAC-CE messages are provided.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a MAC-CE message containing at least the following parameters: a ‘PUCCH-PC-setting’ ID and a CORESET ID or CORESET group ID or a PUCCH resource group ID. When the UE receives the said MAC-CE message, the UE uses the power control settings indicated by the PUCCH-PC-setting to derive the transmit power of the PUCCH resource(s) associated with the indicated CORESET or CORESET group or PUCCH resource group via higher layer configuration.
For pathloss reference RS updates performed via MAC-CE messages, the ‘PUCCH-PathlossReferenceRS’ IEs configured according to 3GPP Rel. 15 may also be used.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a MAC-CE message containing at least the following parameters: a ‘PUCCH-PC-setting’ ID, a pathloss reference RS ID or a ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Rel. 15 and, a CORESET ID or a CORESET group ID or a PUCCH resource group ID. When the UE receives the MAC-CE message, the UE uses the power control settings in the PUCCH-PC-setting and the pathloss reference RS indicated in the MAC-CE to derive the transmit power of the PUCCH resources associated with the indicated CORESET or CORESET group or PUCCH resource group via higher layer configuration. If the ‘PUCCH-PC-setting’ indicated in the MAC-CE message is configured with a pathloss reference RS, the UE replaces the same with the pathloss reference RS indicated in the MAC-CE message.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, a MAC-CE message containing at least the following parameters: a ‘PUCCH-PC-setting’ ID, a UL-SpatialFilter ID, a CORESET ID or a CORESET group ID or a PUCCH resource group ID, and optionally, a pathloss reference RS ID or the ‘PUCCH-PathlossReferenceRS’ according to 3GPP Rel. 15. When the UE receives the MAC-CE message with the pathloss reference RS ID or the ‘PUCCH-PathlossReferenceRS’ according to 3GPP Rel. 15, the UE applies the indicated UL-SpatialFilter to the indicated PUCCH resources and the power control settings from the indicated PUCCH-PC-setting and the indicated pathloss reference RS are used to derive the transmit power of the PUCCH resource(s) associated with the indicated CORESET or CORESET group or PUCCH resource group via higher layer configuration. If the ‘PUCCH-PC-setting’ indicated in the MAC-CE message is configured with a pathloss reference RS, the UE replaces the same with the pathloss RS indicated in the MAC-CE message. When the UE receives the MAC-CE message without the pathloss reference RS ID, the UE applies the indicated UL-SpatialFilter and the power control settings indicated in ‘PUCCH-PC-setting’ for the transmission of the said PUCCH resources, and the pathloss reference RS for the said PUCCH resources is obtained from one of the following by the UE:
The proposed methods for the MAC-CE-based indication of the pathloss reference RSs for PUSCH and PUCCH, and the usage of a CORESET as a pathloss reference are compatible with 3GPP Rel. 15 configuration of the pathloss reference RSs for PUSCH and PUCCH as described in the respective methods. However, in the case of SRS, there is no list of pathloss reference RSs configured in 3GPP Rel. 15 to be indicated via MAC-CE messages. Each SRS resource set is configured with its own pathloss reference RS parameter. Therefore, for the proposed MAC-CE based update of the pathloss reference RS for the SRS to be used along with pathloss reference RS configuration according to 3GPP Rel. 15, a list of pathloss reference RSs for SRS may be configured.
In accordance with an embodiment, the UE is configured to receive from the gNB or any other network entity, SRS pathloss reference RS IE via a higher layer containing at least the following parameters: an ID unique for the SRS pathloss reference RS and the ID of a DL RS, e.g., a CSI-RS resource or an SSB or a CORESET. The UE may receive up to PSRS≥1 pathloss RS configurations.
Referring to
As previously described and in according to an embodiment, applying the UL beam direction or spatial filter IE includes:
According to an embodiment, in case the UL resource used to indicate the beam direction or spatial filter in the IE is an SRS resource, the ID of an UL bandwidth part, BWP, on which the SRS is transmitted is further included in the IE received by the UE.
According to an embodiment, the method comprises receiving, from the network node, a MAC-CE, message containing the ID of at least one PUCCH resource or SRS resource and the ID of at least one UL beam direction or spatial filter IE; and applying the spatial filter used for the transmission of the UL RS resource or the reception of the DL RS resource configured in the indicated UL beam direction or spatial filter IE for the transmission of the indicated PUCCH resource(s) or SRS resource(s).
The ID of the UL beam direction or spatial filter IE used in the MAC-CE message is indicated via a bitmap, and wherein each bit in the bitmap is associated with one of the configured IEs.
According to an embodiment, the method comprises receiving, from the network node, a UL beam direction or spatial filter IE that comprises a CORESET ID to indicate the beam direction instead of a DL or a UL RS; and applying the UL beam direction or spatial filter IE comprising a CORESET ID to one or more of PUCCH resource(s), SRS resource(s) and/or PUSCH which involves the transmission of the said PUCCH resource(s), SRS resources(s), PUSCH with the same spatial filter as the one used for the reception of PDCCH(s) transmitted on the CORESET.
The method further comprises the transmission of the PUCCH resource(s), SRS resource(s), PUSCH with the spatial filter used for the most recent reception of the PDCCH(s) transmitted on the CORESET.
According to an embodiment, the method further comprises receiving, from the network node, a MAC-CE message comprising the ID of a UL beam direction or spatial filter IE that contains a CORESET ID, and the ID of at least one SRS resource or PUCCH resource; and applying the UL beam direction or spatial filter IE to the SRS resource(s) or PUCCH resource(s) indicated in the MAC-CE message.
The method further comprises receiving, from the network node, a PDCCH, that schedules a PUSCH containing an x-bit field, wherein the x-bit field indicates a UL beam direction or spatial filter IE, and applying the indicated UL beam direction or spatial filter IE to the scheduled PUSCH.
The method further comprises receiving, from the network node, a higher layer configured uplink grant that schedules a PUSCH containing the ID of a UL beam direction or spatial filter IE; and applying the indicated UL beam direction or spatial filter IE to the PUSCH scheduled by the uplink grant.
According to another embodiment, a method performed by a UE comprises receiving, from a network node, a higher layer configuration of at least one downlink RS as a pathloss reference in an IE containing at least the following parameters: an ID unique for the pathloss reference RS and the ID of a DL, Reference Signal, RS; and using said pathloss reference RSs in the configuration of the power control setting(s) and/or in the indication of the pathloss reference for PUCCH resource(s) and either SRS resource(s) or PUSCH or both.
The method further comprises receiving a MAC-CE message, from the network node, containing at least a pathloss reference RS ID or the ID of at least a ‘PUCCH-PathlossReferenceRS’ according to 3GPP Release 15, and the ID(s) of one or more PUCCH resources; and using the DL RS configured in the pathloss reference RS indicated by the MAC-CE message to derive a pathloss factor for calculating the transmit power for the UL transmission of the indicated PUCCH resources.
The method further comprises receiving, from the network node, a PDCCH, containing a pathloss reference RS indicator field whose value maps to one of the at least one higher layer configured pathloss reference RS IE or at least one higher layer configured ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15; and using the RS configured in the at least one indicated pathloss reference RS IE or the ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15 to derive a pathloss factor for the calculation of a transmit power for an UL transmission of a PUCCH resource indicated by a PUCCH resource indicator field in the PDCCH.
The method may further comprise receiving, from the network node, a PDCCH containing a pathloss reference RS indicator field whose value maps to one of the at least one higher layer configured pathloss reference RS IE or at least one higher layer configured ‘PUSCH-PathlossReferenceRS’ ID according to 3GPP Release 15; and using the RS configured in the at least one indicated pathloss reference RS IE or the ‘PUSCH-PathlossReferenceRS’ IE according to 3GPP Release 15 to derive a pathloss factor for the calculation of a transmit power for an UL transmission of a PUSCH, scheduled by the PDCCH.
The method may further comprise, receiving, from the network node, a PDCCH containing a pathloss reference RS indicator field whose value maps to one of the at least one higher layer configured pathloss reference RS IE or at least one higher layer configured ‘PUSCH-PathlossReferenceRS’ ID according to 3GPP Release 15; and using the RS configured in the at least one indicated pathloss reference RS IE or the ‘PUSCH-PathlossReferenceRS’ IE according to 3GPP Release 15 to derive a pathloss factor for the calculation of a transmit power for an UL transmission of a Physical Uplink Shared Channel, PUSCH, scheduled by the PDCCH.
According to an embodiment, the method may further comprise, receiving, from the network node, a pathloss reference RS IE comprising a CORESET ID or a PUCCH/PUSCH/SRS pathloss reference RS parameter/IE according to 3GPP Release 15 comprising a CORESET ID; and when a PUSCH and/or PUCCH resource(s) and/or SRS resource(s) are configured/indicated with a CORESET as a pathloss reference, using the DL RS, configured with ‘qcl-TypeD’ in a TCI-state, indicated for the CORESET, as pathloss reference RS to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the said PUSCH and/or PUCCH resource(s) and/or SRS resource(s).
According to an embodiment, the method may further comprise, the updating of the pathloss reference RS of said PUCCH resource(s) and/or SRS resource(s) and/or PUSCH with the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET at every instance the TCI-state of the CORESET is updated.
According to an embodiment, the method may comprise receiving, from the network node, a MAC-CE message containing at least one pathloss reference RS ID or at least one ‘PUSCH-PathlossReferenceRS’ ID according to 3GPP Release 15, and a SRI-PUSCH-PowerControl ID; and updating the pathloss reference RS to be used with the indicated ‘SRI-PUSCH-PowerControl’ IE with the pathloss reference RS indicated by the MAC-CE message.
According to an embodiment, the method may comprise receiving, from the network node, a MAC-CE message containing at least one pathloss reference RS ID or at least one ‘PUSCH-PathlossReferenceRS’ ID according to 3GPP Release 15, and an UL bandwidth part, BWP, ID; and using the RS configured in the indicated pathloss reference RS to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUSCH
According to an embodiment the method may comprise receiving, from the network node, a MAC-CE message containing at least one pathloss reference RS ID or at least one ‘PUSCH-PathlossReferenceRS’ ID according to 3GPP Release 15 and the value of a sounding reference signal index/indicator, SRI, and using the RS configured in the indicated pathloss reference RS to derive a pathloss factor for the calculation of a transmit power for an UL transmission of the PUSCH if the PUSCH transmission is scheduled with the indicated SRI value in a DCI or an uplink configured grant.
The method may comprise receiving a MAC-CE message, from the network node, containing at least a pathloss reference RS ID and ID(s) of one or more SRS resources or SRS resource sets, and using the DL RS configured in the pathloss reference RS IE to derive the pathloss factor for calculating the transmit power for an UL transmission of the indicated SRS resources or all the SRS resources in the indicated SRS resource sets.
According to an embodiment, a method performed by a UE comprises receiving from the network node, a higher layer configuration of a grouping/association of PUCCH resources: using CORESET ID values or CORESET group ID values, or by using a PUCCH resource group identifier, PUCCH resource group ID, that is derived from the transmit/receive point (TRP) the PUCCH resources are associated with.
If PUCCH resources are grouped via a higher layer configuration using CORESET ID values, the UE uses the same spatial filter for the transmission of the group of PUCCH resources associated with a CORESET via higher layer configuration as for the reception of the PDCCH(s) on the CORESET. The method further comprises transmission of the PUCCH resources with the spatial filter used for the most recent reception of the PDCCH(s) transmitted on the CORESET
If PUCCH resources are grouped via a higher layer configuration using CORESET group ID values, the UE uses the same spatial filter for the transmission of the group of PUCCH resources associated with a CORESET group via higher layer configuration as for the reception of the PDCCH(s) on one of the CORESETs belonging to the CORESET group. According to an embodiment, the method comprises the transmission of the PUCCH resource(s) with the spatial filter used for the most recent reception of the PDCCH(s) transmitted on the said CORESET in the CORESET group.
According to an embodiment, the method further comprises receiving, from a network node, a higher layer parameter that indicates whether the UE shall use the same spatial filter for the reception of the PDCCH(s) on a CORESET and the transmission of a group of PUCCH resources associated via higher layer configuration with the CORESET or the CORESET group the CORESET belongs to.
If PUCCH resources are grouped via a higher layer configuration using CORESET ID values, the UE uses a DL RS configured with ‘qcl-TypeD’ in a TCI-state of a CORESET to derive a pathloss factor for the calculation of a transmit power for an UL transmission of the group of PUCCH resources associated with the CORESET via higher layer configuration.
Instead, if PUCCH resources are grouped via a higher layer configuration using CORESET group ID values, the UE uses the DL RS configured with ‘qcl-TypeD’ in the TCI-state of one of the CORESETs in a CORESET group to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the group of PUCCH resources associated with the CORESET group via higher layer configuration.
According to an embodiment, the method comprises receiving, from the network node, a higher layer parameter to indicate whether the UE shall use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET as the pathloss reference RS of a group of PUCCH resources associated via higher layer configuration with the CORESET or the CORESET group the CORESET belongs to.
According to an embodiment, the method comprises receiving, from a network node, via higher layer, a configuration of an IE comprising a set of parameters used for configuration of an UL beam direction or the spatial filter to be used in a UL transmission; wherein the IE contains at least: an identifier, ID, unique to each IE and an ID of an uplink, UL reference signal, RS resource or a downlink, DL, RS resource; and applying the UL beam direction or spatial filter IE for the transmission of one or more of the PUSCH, PUCCH resource(s) and/or SRS resource(s) which includes: transmission of the said PUSCH and/or PUCCH resource(s) and/or SRS resource(s) with the same spatial filter as the one used for the reception of the DL RS resource or the transmission of the UL RS resource contained in the UL beam direction or spatial filter IE.
According to an embodiment, the method comprises receiving, from the network node, a MAC-CE message that contains at least the following: a serving cell ID, a CORESET ID or a CORESET group ID or a PUCCH resource group ID, an ID of a UL beam direction or spatial filter IE and optionally, an UL BWP ID.
When the UE receives the MAC-CE message with a CORESET ID or a CORESET group ID and without an UL BWP ID, the UE applies the UL beam direction or spatial filter IE to the PUCCH resources associated with the indicated CORESET or CORESET group via higher layer configuration or to any PUCCH resource(s) indicated via the PUCCH resource indicator field by PDCCH(s) transmitted on the indicated CORESET or on the CORESET(s) belonging to the indicated CORESET group, and wherein the serving cell ID indicates the cell the MAC-CE message is intended for.
When the UE receives the MAC-CE message with a PUCCH resource group ID and without an UL BWP ID, the UE applies the UL beam direction or spatial filter IE to the PUCCH resources configured with the indicated PUCCH resource group ID.
If the MAC-CE is received with an UL BWP ID, the UL beam direction or spatial filter IE is applied to the said PUCCH resources configured only within the indicated UL BWP.
According to an embodiment, the method may further comprise receiving, from a network node, a higher layer configuration of at least one downlink RS, as a pathloss reference in an IE containing at least the following parameters: an ID unique for the pathloss reference RS and an ID of a DL RS; and receiving, a MAC-CE message, from the network node, containing the ID of at least one said pathloss reference RS IE or the ID of at least one ‘PUCCH-PathlossReferenceRS’ according to 3GPP Release 15, and a CORESET ID or a CORESET group ID or a PUCCH resource group ID; and using the DL RS configured in the pathloss reference RS indicated in the MAC-CE message to derive a pathloss factor for calculating of a transmit power for an UL transmission of a group of PUCCH resources associated via higher layer configuration with CORESET ID or CORESET group or PUCCH resource group indicated in the MAC-CE message or to any PUCCH resource(s) indicated via the PUCCH resource indicator field by PDCCH(s) transmitted on the CORESET or on the CORESET(s) belonging to the CORESET group indicated in the MAC-CE message.
If the MAC-CE is received with an UL BWP ID, the DL RS configured in the pathloss reference RS indicated in the MAC-CE message is used to derive a pathloss factor for calculating of a transmit power for an UL transmission of said PUCCH resources that are configured in the indicated UL BWP.
According to an embodiment, a method performed by a UE comprising receiving, from a network node, an IE, via a higher layer, of one or more power control settings for a PUCCH, PUCCH-PC-setting, wherein a power control setting contains at least the following parameters: an ID unique for each power control setting IE, a closed loop power control index, a p0-PUCCH-ID and optionally the ID of a pathloss reference RS for PUCCH.
According to an embodiment, the method further comprises receiving, from the network node, in a MAC-CE message, at least the following parameters: a PUCCH-PC-setting ID and one or more PUCCH resource IDs; and applying the power control settings indicated by the PUCCH-PC-setting to PUCCH resource(s) indicated in the MAC-CE message to derive a transmit power for said PUCCH resources in an UL transmission.
According to an embodiment, the method further comprises receiving, from a network node, a higher layer configuration of at least one downlink RS as a pathloss reference in an IE containing at least the following parameters: an ID unique for the pathloss reference RS and the ID of a DL Reference Signal, RS or the ID of a CORESET; and when a PUSCH/PUCCH resource/SRS resource is configured/indicated with a pathloss reference RS IE, using the DL RS in the pathloss reference RS IE as a pathloss reference to derive the pathloss factor for the transmission of the said PUSCH/PUCCH resource/SRS resource, or using the DL RS configured with ‘qcl-TypeD’ in a TCI-state, indicated for the CORESET, as pathloss reference RS to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the said PUSCH/PUCCH resource/SRS resource.
According to an embodiment, the method further comprises receiving, from the network node, in a MAC-CE message, at least the following parameters: a PUCCH-PC-setting ID, a pathloss reference RS ID or a ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15 and one or more PUCCH resource IDs; and using the power control settings in the PUCCH-PC-setting and the indicated pathloss reference RS to derive the transmit power for the transmission of the PUCCH resources indicated in the MAC-CE message.
According to an embodiment, the method further comprises receiving, from the network node, via a higher layer, a configuration of an IE comprising a set of parameters used for configuration of an UL beam direction or the spatial filter to be used in a UL transmission; wherein the IE contains at least: an identifier, ID, unique to each IE and an ID of an UL reference signal, RS resource or a DL RS resource.
applying the UL beam direction or spatial filter IE for the transmission of one or more of the PUSCH, PUCCH resource(s) and/or SRS resource(s) which includes: transmission of the said PUSCH and/or PUCCH resource(s) and/or SRS resource(s) with the same spatial filter as the one used for the reception of the DL RS resource or the transmission of the UL RS resource contained in the UL beam direction or spatial filter IE.
According to an embodiment, the method may further comprise receiving from the network node, in a MAC-CE message, at least the following parameters: a PUCCH-PC-setting ID, one or more PUCCH resource IDs, a UL beam direction or spatial filter ID, and optionally, a pathloss reference RS ID or a ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15.
If the MAC-CE message contains the pathloss reference RS ID or the ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15, applying the indicated UL beam direction or spatial filter to the indicated PUCCH resources, and the power control settings in the indicated PUCCH-PC-setting and the pathloss reference RS indicated in the MAC-CE message are used to derive the transmit power for the transmission of the indicated PUCCH resources
If the MAC message is received without a pathloss reference RS ID or a ‘PUCCH-PathlossReferenceRS’ ID, applying the indicated UL beam direction or spatial filter and the power control settings indicated in ‘PUCCH-PC-setting’ to the indicated PUCCH resources, and obtaining the pathloss reference RS for the derivation of the pathloss factor for the transmission of the indicated PUCCH resources from one of the following:
when the indicated UL beam direction or spatial filter IE is configured with a CORESET ID, the DL RS configured with ‘qcl-typeD’ in the TCI-state of the said CORESET.
If both the MAC-CE message and the ‘PUCCH-PC-setting’ indicated in the MAC-CE message indicate a pathloss reference RS, the UE uses the pathloss reference RS indicated in the MAC-CE message in the derivation of the transmit power for the transmission of the indicated PUCCH resources.
According to an embodiment, the method further comprises a higher layer configuration of a grouping/association of PUCCH resources:
using CORESET ID values or CORESET group ID values, or by using a PUCCH resource group identifier, PUCCH resource group ID, that is derived from the transmit/receive point (TRP) the PUCCH resources are associated with.
According to an embodiment, the method may further comprise receiving, from the network node, a MAC-CE message, containing at least the following parameters: a PUCCH-PC-setting ID and a CORESET ID or CORESET group ID or a PUCCH resource group ID. When the UE receives the MAC-CE message, the UE applies the power control settings indicated by the PUCCH-PC-setting to the PUCCH resource(s) associated via higher layer configuration with the indicated CORESET or CORESET group or PUCCH resource group.
According to an embodiment, the method may further comprise receiving from the network node, in a MAC-CE message, at least the following parameters: a PUCCH-PC-setting ID, a pathloss reference RS ID or a ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15, and a CORESET ID or a CORESET group ID or a PUCCH resource group ID.
When the UE receives the MAC-CE message, the UE uses the power control settings in the PUCCH-PC-setting and the indicated pathloss reference RS assumption for the transmission of the PUCCH resources associated via higher layer configuration with the indicated CORESET or CORESET group or PUCCH resource group, if the ‘PUCCH-PC-setting’ indicated in the MAC-CE message is configured with a pathloss reference RS, the UE ignores it to use the pathloss reference RS indicated in the MAC-CE message to derive the pathloss factor for the transmission of the said PUCCH resources.
According to an embodiment, the method may further comprise receiving from the network node, in a MAC-CE message, at least the following parameters: a ‘PUCCH-PC-setting’ ID, a UL beam direction or spatial filter ID, a CORESET ID or a CORESET group ID or a PUCCH resource group ID, and optionally, a pathloss reference RS ID or the ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15.
When the UE receives said MAC-CE message with a pathloss reference RS ID or a ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15, the UE applies the indicated UL beam direction or spatial filter to the indicated PUCCH resources, and the power control settings from the indicated PUCCH-PC-setting and the indicated pathloss reference RS are used to derive the transmit power for the transmission of the PUCCH resource(s) associated via higher layer configuration with the indicated CORESET or CORESET group or PUCCH resource group.
According to an embodiment, if the MAC message is received without a pathloss reference RS ID or a ‘PUCCH-PathlossReferenceRS’ ID according to 3GPP Release 15, applying the indicated UL beam direction or spatial filter and the power control settings indicated in ‘PUCCH-PC-setting’ to the said PUCCH resources, and obtaining the pathloss reference RS for the derivation of the pathloss factor for the transmission of the said PUCCH resources from one of the following:
According to another embodiment, a method performed by a UE comprising using the spatial filter used for the reception of the PDCCH(s) on a CORESET for the transmission of PUCCH resource(s) indicated in the PUCCH resource indicator field of the PDCCH(s) transmitted on the CORESET.
According to another embodiment, the method may further comprise using the spatial filter used for the reception of the PDCCH(s) on a CORESET for the transmission of the PUCCH resource(s) indicated in the PUCCH resource indicator field of the PDCCH(s) transmitted on the CORESET, when the PUCCH resource(s) is (are) not configured/indicated with a spatial filter/spatial relation information.
According to another embodiment, the method may further comprise receiving, from a network node, a higher layer parameter that indicates whether the spatial filter used by the UE for the reception of the PDCCH(s) on a CORESET is used for the transmission of the PUCCH resource(s) indicated in the PUCCH resource indicator field of the PDCCH(s) transmitted on the CORESET.
According to another embodiment, a method performed by a UE comprising using the spatial filter used for the reception of a PDSCH for the transmission of the PUCCH resource(s) that carry the HARQ ACK/NACK for the PDSCH.
According to another embodiment, the method may further comprise using the spatial filter used for the reception of a PDSCH for the transmission of the PUCCH resource(s) that carry the HARQ ACK/NACK for the PDSCH, when the PUCCH resource(s) is (are) not configured/indicated with a spatial filter/spatial relation information.
According to another embodiment, the method may further comprise receiving, from a network node, a higher layer parameter that indicates whether the spatial filter used by the UE for the reception of a PDSCH is used for the transmission of the PUCCH resource(s) that carry the HARQ ACK/NACK for the PDSCH.
According to another embodiment, a method performed by a UE comprising using the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource(s) indicated by the PUCCH resource indicator field in the PDCCH(s) transmitted on the CORESET.
According to another embodiment, the method may further comprise using the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource(s) indicated by the PUCCH resource indicator field in the PDCCH(s) transmitted on the CORESET, when there is no configuration/indication of pathloss reference RS(s) for the PUCCH resource(s).
According to another embodiment, the method may further comprise receiving, from a network node, a higher layer parameter that indicates whether the UE shall use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a CORESET to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resources indicated by the PUCCH resource indicator field in the PDCCH(s) transmitted on the CORESET.
According to another embodiment, a method performed by a UE comprising using the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a PDSCH to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource(s) that carries the HARQ ACK(s)/NACK(s) for the PDSCH.
According to another embodiment, the method may further comprise using the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a PDSCH to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource(s) that carries the HARQ ACK(s)/NACK(s) for the PDSCH, when there is no configuration/indication of pathloss reference RS(s) for the PUCCH resource(s).
According to another embodiment, the method may further comprise receiving, from a network node, a higher layer parameter that indicates whether the UE shall use the DL RS configured with ‘qcl-TypeD’ in the TCI-state of a PDSCH to derive the pathloss factor for the calculation of the transmit power for an UL transmission of the PUCCH resource that carries the HARQ ACK(s)/NACK(s) for the PDSCH.
According to another embodiment, a method performed by a UE comprising
The method further comprises: receiving a MAC-CE message, from the network node, containing at least a pathloss reference RS ID and ID(s) of one or more SRS resources or SRS resource sets, and using the DL RS configured in the pathloss reference RS IE to derive a pathloss factor for calculating transmit power of UL transmission of the indicated SRS resources or all the SRS resources in the indicated SRS resource sets.
In order to perform the previously described process or method steps, there is also provided a UE.
The UE 900 may belong to any radio access technology including 4G or LTE, LTE-A, 5G, etc. that support beamforming technology. The UE comprising a processor and a memory contains instructions executable by the processor, whereby the UE is operative to perform any on of the subject-matter of claims 1-53.
Details on the functions and operations performed by the UE have already been described and need not be repeated.
There is also provided a method performed by a network node (e.g. a gNB) or any suitable network entity. Details of the actions performed by the network node or gNB or any suitable network entity for configuring the UE according to the previously described embodiment have already been presented.
The network node or gNB comprises a processor or processing circuit or a processing module or a processor or means; a receiver circuit or receiver module; a transmitter circuit or transmitter module; a memory module a transceiver circuit or transceiver module which may include the transmitter circuit and the receiver circuit. The gNB further comprises an antenna system which includes antenna circuitry for transmitting and receiving/transmitting signals to/from at least the UE. The antenna system employs beamforming as previously described. The gNB may operate in any radio access technology including 2G, 3G, 4G or LTE, LTE-A, 5G, WLAN, and WiMax etc. that support beamforming technology.
The processing module/circuit includes a processor, microprocessor, an application specific integrated circuit (ASIC), field programmable gate array (FPGA), or the like, and may be referred to as the “processor.” The processor controls the operation of the gNB and its components. Memory (circuit or module) includes a random access memory (RAM), a read only memory (ROM), and/or another type of memory to store data and instructions that may be used by processor. In general, it will be understood that the gNB in one or more embodiments includes fixed or programmed circuitry that is configured to carry out the operations in any of the embodiments disclosed herein.
In at least one such example, the gNB includes a microprocessor, microcontroller, DSP, ASIC, FPGA, or other processing circuitry that is configured to execute computer program instructions from a computer program stored in a non-transitory computer-readable medium that is in, or is accessible to the processing circuitry. Here, “non-transitory” does not necessarily mean permanent or unchanging storage, and may include storage in working or volatile memory, but the term does connote storage of at least some persistence. The execution of the program instructions specially adapts or configures the processing circuitry to carry out the operations disclosed in this disclosure. Further, it will be appreciated that the gNB may comprise additional components.
Throughout this disclosure, the word “comprise” or “comprising” has been used in a non-limiting sense, i.e. meaning “consist at least of”. Although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. The embodiments herein may be applied in any wireless systems including LTE or 4G, LTE-A (or LTE-Advanced), 5G, WiMAX, WiFi, satellite communications, TV broadcasting etc. that may employ beamforming technology.
This application is a continuation of U.S. patent application Ser. No. 17/635,150 filed on Feb. 14, 2022 which is the U.S. National Phase application under 35 U.S.C. § 371 of International Application No. PCT/EP2019/071964 filed on Aug. 15, 201920/050003 filed on Jan. 2, 2020. These applications are hereby incorporated by reference herein.
Number | Date | Country | |
---|---|---|---|
Parent | 17635150 | Feb 2022 | US |
Child | 19001642 | US |