US-12628086-B2 - MAC CE for power control for uplink transmissions towards multiple TRPs

US12628086B2US 12628086 B2US12628086 B2US 12628086B2US-12628086-B2

Abstract

Systems and methods for activating or updating power control parameters are provided. In some embodiments, a method performed by a wireless communication device comprises a method performed by a wireless communication device comprises receiving an indication of activated Transmission Configuration Indicator (TCI) states for physical uplink channels or uplink reference signals via a first Medium Access Control (MAC) Control Element (CE) message; receiving one or more power control parameter lists each comprising a plurality of elements; obtaining power control state information via a second MAC CE message that maps a power control state. The power control state information comprises indications each indicating a particular element from among the plurality of elements in one of the one or more power control parameter lists; and transmitting each of the physical uplink channels or uplink reference signals according to the active TCI states and the respective power control state information.

Inventors

Helka-Liina Määttänen
Shiwei Gao
Siva Muruganathan
Andreas Nilsson

Assignees

TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

Dates

Publication Date: 20260512
Application Date: 20210804

Claims (19)

1 . A method performed by a wireless communication device, comprising: receiving an indication of one or more activate Transmission Configuration Indicator, TCI, states for a plurality of physical uplink channels or uplink reference signals via a first Medium Access Control, MAC, Control Element, CE, message; receiving, for each of the plurality of physical uplink channels or uplink reference signals, one or more power control parameter lists each comprising a plurality of elements, where each element in the one or more power control parameter lists comprises one or more values for one or more respective power control parameters; obtaining, for each of the one or more activate TCI states and each of the plurality of physical uplink channels or uplink reference signals, power control state information via a second MAC CE message that maps a power control state, the power control state information comprising one or more indications each indicating a particular element from among the plurality of elements in one of the one or more power control parameter lists such that the one or more values for the one or more respective power control parameters comprised in the particular element are indicated for the power control state; and transmitting each of the plurality of physical uplink channels or uplink reference signals according to the one or more active TCI states and the respective power control state information; wherein each of the plurality of elements of the one or more power control parameter lists comprises a set of values for two or more power control parameters.
2 . The method of claim 1 , wherein receiving an indication of one or more active TCI states comprises receiving an indication in a Downlink Control Information, DCI, format in addition to the first MAC CE message.
3 . The method of claim 2 , wherein the update of a power control parameter is to be applied to the power control state and one or more additional power control states indicted in the third MAC CE message.
4 . The method of claim 1 , wherein the plurality of physical uplink channels can be two or more of a Physical Uplink Shared Channel, PUSCH, a Physical Uplink Control Channel, PUCCH; and the plurality of uplink reference signals can be two or more of a Sounding Reference Signal, SRS.
5 . The method of claim 1 , wherein receiving one or more power control parameter lists comprises receiving the one or more power control parameter lists via Radio Resource Control, RRC, signaling.
6 . The method of claim 1 , wherein the first MAC CE message and the second MAC CE message are separate control messages.
7 . The method of claim 1 , wherein the first MAC CE message and the second MAC CE message are the same control message.
8 . The method of claim 1 further comprising receiving an update via a third MAC CE message for the power control state, the update comprising one or more new indications each indicating a new particular element from among the plurality of elements in one of the one or more power control parameter lists such that the one or more values for the one or more respective power control parameters comprised in the new particular element are used to replace the existing one or more values for the one or more respective power control parameters in the power control state.
9 . The method of claim 1 , wherein the third MAC CE message is the same as the second MAC CE message.
10 . The method of claim 1 wherein the plurality of elements in each of the one or more power control parameter lists comprise different values for the one or more respective power control parameters.
11 . The method of claim 1 wherein the one or more power control parameters comprise one or more of P 0 , α, a closed loop index, and a pathloss Reference Signal, RS.
12 . The method of claim 1 wherein the method further comprises receiving, for each of the plurality of physical uplink channels or uplink reference signals, a mapping between one of the one or more active TCI states and one of a plurality of power control states for the respective physical uplink channel or uplink reference signal.
13 . The method of claim 1 wherein the power control state information further comprises a list of one or more active TCI state identifiers associated to the power control state.
14 . The method of claim 1 wherein the two or more power control parameters comprise: P 0 and α; P 0 and a closed loop index; α and a closed loop index; or P 0 , α, and a closed loop index.
15 . A wireless communication device comprising: one or more transmitters; one or more receivers; and processing circuitry associated with the one or more transmitters and the one or more receivers, the processing circuitry configured to cause the wireless communication device to: receive an indication of one or more activate Transmission Configuration Indicator, TCI, states for a plurality of physical uplink channels or uplink reference signals via a first Medium Access Control, MAC, Control Element, CE, message; receive, for each of the plurality of physical uplink channels or uplink reference signals, one or more power control parameter lists each comprising a plurality of elements, where each element in the one or more power control parameter lists comprises one or more values for one or more respective power control parameters; obtain, for each of the one or more activate TCI states and each of the plurality of physical uplink channels or uplink reference signals, power control state information via a second MAC CE message that maps a power control state, the power control state information comprising one or more indications each indicating a particular element from among the plurality of elements in one of the one or more power control parameter lists such that the one or more values for the one or more respective power control parameters comprised in the particular element are indicated for the power control state; and transmit each of the plurality of physical uplink channels or uplink reference signals according to the one or more active TCI states and the respective power control state information; wherein each of the plurality of elements of the one or more power control parameter lists comprises a set of values for two or more power control parameters.
16 . A method performed by a wireless communication device, comprising: obtaining a first power control parameter list comprising a plurality of elements, where each element in the first power control parameter list comprises one or more values for one or more respective power control parameters; and receiving information that indicates an association between an activated Transmission Configuration Indicator, TCI, state and a particular element from among the plurality of elements in the first power control parameter list; wherein each of the plurality of elements of the one or more power control parameter lists comprises a set of values for two or more power control parameters.
17 . The method of claim 16 further comprising using the one or more values for the one or more respective power control parameters in the particular element of the first power control parameter list for an uplink transmission associated to the activated TCI state.
18 . The method of claim 16 wherein receiving the information that indicates the association between the activated TCI state and the particular element from among the plurality of elements in the first power control parameter lists comprises: receiving a message that activates the TCI state, the TCI state being mapped to a respective TCI state to power control identifier; and receiving, for the TCI state to power control identifier, an indication of the particular element from among the plurality of elements in the first power control parameter list such that the one or more values for the one or more respective power control parameters comprised in the particular element of the first power control parameter list are indicated for the TCI state to power control ID and thus associated to the activated TCI state.
19 . A wireless communication device comprising: one or more transmitters; one or more receivers; and processing circuitry associated with the one or more transmitters and the one or more receivers, the processing circuitry configured to cause the wireless communication device to: obtain a first power control parameter list comprising a plurality of elements, where each element in the first power control parameter list comprises one or more values for one or more respective power control parameters; and receive information that indicates an association between an activated Transmission Configuration Indicator, TCI, state and a particular element from among the plurality of elements in the first power control parameter list; wherein each of the plurality of elements of the one or more power control parameter lists comprises a set of values for two or more power control parameters.

Description

RELATED APPLICATIONS This application is a 35 U.S.C. § 371 national phase filing of International Application No. PCT/IB2021/057168, filed Aug. 4, 2021, which claims the benefit of provisional patent application Ser. No. 63/061,710, filed Aug. 5, 2020, the disclosures of which are hereby incorporated herein by reference in their entireties. TECHNICAL FIELD The present disclosure relates to activating or updating power control parameters associated with Uplink (UL) Transmission Configuration Indicator (TCI) states. BACKGROUND The next generation mobile wireless communication system (5G), or new radio (NR), will support a diverse set of use cases and a diverse set of deployment scenarios. The later includes deployment at both low frequencies (below 6 GHz) and very high frequencies (up to 10's of GHz). NR Frame Structure and Resource Grid NR uses Cyclic Prefix Orthogonal Frequency Division Multiplexing (CP-OFDM) in both downlink (DL) (i.e., from a network node (gNB) or a base station, to a user equipment (UE)) and uplink (UL) (i.e., from UE to gNB). Discrete Fourier Transform (DFT) spread OFDM is also supported in the uplink. In the time domain, NR downlink and uplink are organized into equally sized subframes of 1 ms each. A subframe is further divided into multiple slots of equal duration. The slot length depends on subcarrier spacing. For subcarrier spacing of Δf=15 kHz, there is only one slot per subframe, and each slot consists of 14 OFDM symbols. Data scheduling in NR is typically in slot basis, an example is shown in FIG. 1 with a 14-symbol slot, where the first two symbols contain Physical Downlink Control Channel (PDCCH) and the rest contains physical shared data channel, either Physical Downlink Shared Channel (PDSCH) or Physical Uplink Shared Channel (PUSCH). Different subcarrier spacing values are supported in NR. The supported subcarrier spacing values (also referred to as different numerologies) are given by Δf=(15×2μ) kHz where μ∈{0,1,2,3,4}. Δf=15 kHz is the basic subcarrier spacing. The slot durations at different subcarrier spacings is given by 12⁢μ⁢ ms. In the frequency domain, a system bandwidth is divided into resource blocks (RBs), each corresponds to 12 contiguous subcarriers. The RBs are numbered starting with 0 from one end of the system bandwidth. The basic NR physical time-frequency resource grid is illustrated in FIG. 2, where only one RB within a 14-symbol slot is shown. One OFDM subcarrier during one OFDM symbol interval forms one resource element (RE). DL PDSCH transmissions can be either dynamically scheduled, i.e., in each slot the gNB transmits Downlink Control Information (DCI) over PDCCH about which UE data is to be transmitted to and which RBs in the current downlink slot the data is transmitted on, or semi-persistently scheduled (SPS) in which periodic PDSCH transmissions are activated or deactivated by a DCI. Different DCI formats are defined in NR for DL PDSCH scheduling including DCI format 1_0, DCI format 1_1, and DCI format 1_2. Similarly, UL PUSCH transmission can also be scheduled either dynamically or semi-persistently with uplink grants carried in PDCCH. NR supports two types of semi-persistent uplink transmission, i.e., type 1 configured grant (CG) and type 2 configured grant, where Type 1 configured grant is configured and activated by Radio Resource Control (RRC) while type 2 configured grant is configured by RRC but activated/deactivated by DCI. The DCI formats for scheduling PUSCH include DCI format 0_0, DCI format 0_1, and DCI format 0_2. Transmission with Multiple Beams In high frequency range (FR2), multiple radio frequency (RF) beams may be used to transmit and receive signals at a gNB and a UE. For each DL beam from a gNB, there is typically an associated best UE Rx beam for receiving signals from the DL beam. The DL beam and the associated UE Rx beam forms a beam pair. The beam pair can be identified through a so-called beam management process in NR. A DL beam is identified by an associated DL Reference Signal (RS) transmitted in the beam, either periodically, semi-persistently, periodically. The DL RS for the purpose can be a Synchronization Signal (SS) and Physical Broadcast Channel (PBCH) block (SSB) or a Channel State Information Reference Signal (CSI-RS). For each DL RS, a UE can do an Rx beam sweep to determine the best Rx beam associate with the DL beam. The best Rx beam for each DL RS is then memorized by the UE. By measuring all the DL RSs, the UE can determine and report to the gNB the best DL beam to use for DL transmissions. With the reciprocity principle, the same beam pair can also be used in the UL to transmit a UL signal to the gNB, often referred to as beam correspondence. An example is shown in FIG. 3, where a gNB consists of a transmission/reception point (TRP) with two DL beams each associated with a CSI-RS and one SSB beam. Each of the DL beams is associated with a best UE Rx beam, i.e., Rx beam #1 is associated with the DL beam w