CN114145063A

CN114145063A - User equipment and method for backing off physical uplink shared channel transmission

Info

Publication number: CN114145063A
Application number: CN202080053017.7A
Authority: CN
Inventors: 郭力
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2019-07-22
Filing date: 2020-07-13
Publication date: 2022-03-04
Also published as: WO2021012977A1

Abstract

The embodiment of the present application relates to a User Equipment (UE) and a method for fallback transmission of a Physical Uplink Shared Channel (PUSCH). The method includes a UE being configured or indicated by a Base Station (BS) with a first transmit (Tx) beam and a second transmit (Tx) beam, wherein the first Tx beam and the second Tx beam are configured for transmission over a Physical Uplink Control Channel (PUCCH), and the UE transmitting the first Tx beam on PUCCH resources in a first PUCCH resource group and the UE transmitting the second Tx beam on PUCCH resources in a second PUCCH resource group.

Description

User equipment and method for backing off physical uplink shared channel transmission

Technical Field

The present application relates to the field of communication systems, and in particular, to a User Equipment (UE) and a method for fallback to a Physical Uplink Shared Channel (PUSCH).

Background

In the current design, a transmit (Tx) beam determination method is not applicable to a Tx beam indication new design of a Physical Uplink Control Channel (PUCCH) resource, where the Tx beam determination method is used for a Downlink Control Information (DCI) format scheduled PUSCH, and the DCI format includes DCI format 0_ 0. In particular, the current Tx beam indication design for PUSCH scheduled for DCI format 0_0 is not applicable to the case of multiple Transmission and Reception Points (TRPs).

Therefore, there is a need for a UE and a method of fallback PUSCH transmission.

Disclosure of Invention

The application provides a UE and a method for backing off PUSCH transmission, which can provide signaling with high reliability, low overhead and low delay so as to support the PUSCH transmission based on a DCI format in a multi-TRP system.

In a first aspect of the present application, a method for fallback PUSCH of a UE is provided. The method includes a UE being configured or indicated by a Base Station (BS) with a first Tx beam and a second Tx beam, wherein the first Tx beam and the second Tx beam are configured for transmission over PUCCH, and the UE transmitting the first Tx beam on PUCCH resources in a first PUCCH resource group and the UE transmitting the second Tx beam on PUCCH resources in a second PUCCH resource group.

In a second aspect of the present application, a UE for fallback PUSCH transmission is provided. The UE includes a memory, a transceiver, and a processor coupled to the memory and the transceiver. Wherein the processor is configured or indicated by the BS with a first Tx beam and a second Tx beam configured for transmission over PUCCH, and the UE transmits the first Tx beam on a PUCCH resource in a first PUCCH resource group and the UE transmits the second Tx beam on a PUCCH resource in a second PUCCH resource group.

In a third aspect of the present application, there is provided a non-transitory machine-readable storage medium having stored thereon instructions which, when executed by a computer, cause the computer to perform the above-described method.

In a fourth aspect of the present application, there is provided a chip comprising a processor configured to call and run a computer program stored in a memory to cause a device in which the chip is installed to perform the above method.

In a fifth aspect of the present application, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program causes a computer to execute the above-mentioned method.

In a sixth aspect of the application, a computer program product is provided, comprising a computer program, wherein the computer program causes a computer to perform the above-mentioned method.

In a seventh aspect of the present application, a computer program is provided, which causes a computer to perform the above method.

Drawings

In order to more clearly describe embodiments of the present invention or related techniques, the embodiments will be briefly described below with reference to the accompanying drawings. It is clear that the figures are only some embodiments of the invention, from which other figures can be derived by a person skilled in the art without any further elaboration.

Fig. 1 is a block diagram of a transmitter for downlink or uplink transmission.

Fig. 2 is a block diagram of a receiver for receiving downlink or uplink transmissions.

Fig. 3 is a block diagram of a UE and a BS for fallback PUSCH transmission provided by an embodiment of the present application.

Fig. 4 is a flowchart of a method for fallback PUSCH transmission for a UE according to an embodiment of the present application.

Fig. 5 is a flowchart of a method for determining a spatial relationship of a PUSCH transmission scheduled by a DCI format including DCI format 0_0 provided in an embodiment of the present application.

Fig. 6 is a block diagram of a system for wireless communication provided by an embodiment of the application.

Detailed Description

Technical matters, structural features, attained objects, and effects of the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Specifically, the terminology used in the embodiments of the present invention is for the purpose of describing the embodiments of the present invention only and is not intended to be limiting of the invention.

A 5G wireless system is typically a multi-beam based system within a frequency range 2(FR 2) from 24.25GHz to 52.6GHz, where a base station and/or user equipment uses multiplexed Tx and receive (Rx) analog beams to combat large path losses in the high frequency band. In high frequency band systems, such as millimeter wave systems, base stations and user equipment are deployed with a large number of antennas, so that large gain beamforming can be used to overcome large path loss and signal shadowing. Due to hardware limitations and cost, base stations and user equipment may be equipped with only a limited number of transmit and receive units (TXRUs). Therefore, the hybrid beamforming mechanism can be used in both the base station and the user equipment. In order to obtain the best link quality between the base station and the user equipment, the base station and the user equipment need to align the direction of the analog beam for a particular downlink or uplink transmission. For downlink transmission, the base station and the user equipment need to find the best pair of base station transmit beam and user equipment receive beam, and for uplink transmission, the base station and the user equipment need to find the best pair of user equipment transmit beam and base station receive beam.

For communication between a user equipment and a base station, the base station and the user equipment need to determine which transmit and receive beams are to be used. When a user equipment moves, the beams used by the base station and the user equipment for communication may change. In the 3GPP5G specification, the following functions are defined to support such multi-beam based operation.

In operation associated with beam measurement and reporting, in this function, the user equipment may measure one or more transmit beams of the base station, and the user equipment may then select and report the best transmit beam selection to the base station. By measuring the transmit beam of the base station, the user equipment may also measure one or more different receive beams and then select the best receive beam for a particular transmit beam of the base station. In this function, the gNB may also measure one or more transmit beams of the user equipment and then select the best transmit beam for the user equipment for uplink transmission. To support measuring the transmit beams of the base station, the BS may transmit multiple Reference Signal (RS) resources and then configure the user equipment to measure the RS resources. Thereafter, the user equipment may report an index of one or more selected RS resources selected based on some metric (e.g., layer 1reference signal received power, L1-RSRP). To support measurement of a transmit beam of a user equipment for uplink transmission, a base station may configure the user equipment to transmit one or more uplink RS resources (e.g., Sounding Reference Signal (SRS) resources), which the base station may then measure. The base station may determine which transmit beam of the user equipment is best for uplink transmission based on measuring, for example, L1-RSRP of the RS resource.

In operation associated with beam indication, for a downlink transmission, the base station may instruct the user equipment which transmit beam of the base station to use for transmission so that the user equipment may receive the downlink transmission using the appropriate receive beam. For Physical Downlink Control Channel (PDCCH) transmission, the base station may indicate to the user equipment an Identity (ID) of one transmission beam of the base station. For physical downlink discovery channel (PSDCH) transmission, the base station may use DCI in the PDCCH to indicate the identity of one transmission beam used to transmit the corresponding PDSCH. The base station may also instruct the user equipment which transmit beam to use for uplink transmissions from the user equipment. For example, for PUCCH transmission, the user equipment uses a transmission beam indicated by the base station through configuration of spatial relationship information. For SRS transmission, the user equipment uses a transmission beam indicated by the base station through configuration of the spatial relationship information. For PUSCH transmission, the user equipment uses the transmit beam indicated by the information element contained in the scheduling DCI.

In operations associated with beam switching, the base station uses this function to switch transmit beams for downlink or uplink transmissions. This functionality is useful when the transmit beam currently used for transmission is out of date due to, for example, movement of the user equipment. When the base station finds that a transmission beam currently used for downlink transmission is not good or finds another transmission beam better than the current transmission beam, the base station may send signaling to the user equipment to inform of the change of the transmission beam. Similarly, the base station may switch uplink transmit beams for user equipments transmitting some uplink transmissions.

In a communication system such as a New Radio (NR) system, a downlink signal may include control signaling for transmitting DCI through a PDCCH, a data signal for transmitting an information packet through a PDSCH, and some types of reference signals. The DCI may indicate information on how the PDSCH is transmitted, including, for example, resource allocation and transmission parameters for the PDSCH. The base station may transmit one or more types of reference signals for different purposes, including: a demodulation reference signal (DM-RS) transmitted with the PDSCH and usable by the user equipment to demodulate the PDSCH, a channel state information reference signal (CSI-RS) usable by the user equipment to measure a transmission beam of the base station or CSI of a downlink channel between the base station and the user equipment, and a phase tracking reference signal (PT-RS) also transmitted with the PDSCH and usable by the user equipment to estimate phase noise caused by imperfections of radio frequency parts in the transmitter and receiver and then compensate for it when decoding the PDSCH. In NR, downlink resource allocation for a PDCCH, a PDSCH, and a reference signal is performed in units of Orthogonal Frequency Division Multiplexing (OFDM) symbols and a set of Physical Resource Blocks (PRBs). Each PRB includes several Resource Elements (REs), for example 12 REs, in the frequency domain. A transmission Bandwidth (BW) for a downlink transmission consists of frequency resource elements called Resource Blocks (RBs), and each RB consists of several subcarriers or REs (e.g., 12 subcarriers or REs).

The UL signal transmitted by the user equipment to the base station may include: a data signal for transmitting a data packet through a PUSCH, an uplink control signal for transmitting UL Control Information (UCI) that can be transmitted in a PUSCH or a PUCCH, and a UL reference signal. The UCI may carry a Scheduling Request (SR) for requesting uplink transmission resources by the ue, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback for PDSCH transmission, or a Channel State Information (CSI) report. The user equipment may transmit one or more types of uplink reference signals for different purposes, including: DM-RS transmitted with PUSCH transmission and usable by the base station to demodulate PUSCH, PT-RS also transmitted with PUSCH and usable by the base station to estimate phase noise caused by imperfections in the radio frequency part which the base station can then compensate for when decoding PUSCH, and SRS signals used by the base station to measure CSI for one or more user equipment transmit beams or uplink channels between the user equipment and the base station. Similarly, UL resource allocation for PUSCH, PUCCH, and UL reference signals is also performed in units of symbols and a set of PRBs.

The transmission interval for a DL or UL channel/signal is called a slot, and each slot contains several (e.g., 14) symbols in the time domain. In the NR system, the duration of one slot may be 1, 0.5, 0.25, or 0.123 msec for subcarrier intervals of 15KHz, 30KHz, 60KHz, and 120KHz, respectively. NR systems support a flexible set of base parameters and embodiments may select a suitable OFDM subcarrier spacing based on deployment scenarios and service requirements. In NR systems, DL and UL transmissions may use different sets of base parameters.

Fig. 1 shows a block diagram of a transmitter for downlink or uplink transmission. The embodiment of the transmitter block shown in fig. 1 is for illustration only. Other embodiments may be used without departing from the scope of this disclosure. Information bits 001 may first be encoded by an encoder 002 (e.g., a Low Density Parity Check (LDPC) encoder or a polar encoder) and then modulated by a modulator 003. The modulation may be, for example, binary phase-shift keying (BPSK), Quadrature Amplitude Modulation (QAM) 4, QAM 16, QAM 64, or QAM 256. Then, serial to parallel (S/P) converter 004 can generate parallel multiple modulation symbols, which are then input to RE mapper and precoder 005. The RE mapper and precoder 005 may map modulation symbols to selected REs and then apply a certain precoder to modulation symbols on the bandwidth resources allocated to DL or UL transmissions. Thereafter, in 006, the modulation symbols are applied with Inverse Fast Fourier Transform (IFFT), and then the output thereof is serialized by parallel to serial (P/S) converter 007. Thereafter, the signal is transmitted to a transmitting unit 008 including, for example, a digital-to-analog (D/a) converter, a radio frequency converter, a filter, a power amplifier, and a transmitting antenna element, and is transmitted.

Fig. 2 shows a block diagram of a receiver for receiving downlink or uplink transmissions. The embodiment of the receiver block shown in fig. 2 is for illustration only. Other embodiments may be used without departing from the scope of this disclosure. The received signal 011 first passes through a receiving unit 012 including, for example, a receiving antenna element, a low noise power amplifier, a radio frequency converter, and a filter. And its output passes through P/S013 and then Fast Fourier Transform (FFT) 014 is applied. After conversion to the frequency domain, the useful signal is extracted by the RE demapping 015 according to the resource allocation for DL or UL transmission. Subsequently, the demodulator 016 demodulates the data symbols using the channel estimation calculated based on the DM-RS, and then the decoder 017 (e.g., an LDPC decoder or a polar decoder) decodes the demodulated data to output information bits 018.

In NR3GPP specification release 15, beam indication is performed per PUCCH resource. For a given uplink partial Bandwidth (BWP) in the serving cell, the UE may be configured with 4 PUCCH resource sets, and in each PUCCH resource set, one or more PUCCH resources. For transmission on each PUCCH resource, the UE is configured with a parameter PUCCH-spatial relationinfo, which may contain one or more reference signal resource IDs. Each of these reference signal resources is used to provide information about which transmit beam the UE may use for transmission on that PUCCH resource. For example, if the reference signal resource is an SRS resource, the UE may transmit on the PUCCH resource using the same Tx beam used to transmit the SRS resource. If the reference signal resource is a CSI-RS resource or a synchronization signal/physical broadcast channel (SS/PBCH) block, the UE may transmit on the PUCCH resource using an uplink Tx beam corresponding to a reception beam used to receive CSI-RS resource transmission or SS/PBCH block transmission. The gNB may configure only one PUCCH-spatial relationship info for the PUCCH resource. When the gNB wants to switch the Tx beam of the PUCCH resource, the gNB may reconfigure Radio Resource Control (RRC) parameters. The gNB may also configure a plurality of PUCCH-spatial relationship info for the PUCCH resource in the RRC, and then deactivate one of the configured PUCCH-spatial relationship info as a current Tx beam of the PUCCH resource using medium access control element (MAC CE) signaling. If the gNB wants to switch Tx beams of one PUCCH resource, the gNB may indicate another PUCCH-spatial relationship info for the PUCCH resource using one MAC CE message. The gmb may indicate PUCCH-spatial relationship info for each individual PUCCH resource using the MAC CE message. The advantage of this approach is that it is flexible and enables the gNB to apply different Tx beams on different PUCCH resources.

For PUSCH scheduled by DCI format 0_0 on a cell, the UE may be requested to transmit the PUSCH according to a spatial relationship corresponding to a dedicated PUCCH resource with a minimum ID within the UL BWP of the cell. In other words, if PUSCH transmission through DCI format 0_0 is scheduled for a UE in one UL BWP, the UE may transmit the PUSCH using a Tx beam configured to a PUCCH with a smallest PUCCH resource ID in the same UL BWP.

In 3GPP release 16, the Tx beam indication/update of PUCCH resources will be changed to be per PUCCH group. In one UL BWP, all PUCCH resources may be divided into one group or two groups. One group use case is single TRP transmission and two groups use case is multiple TRP transmission. Each TRP may schedule PUSCH transmissions for a UE, and the UE may apply a different Tx beam accordingly.

Fig. 3 illustrates a UE10 and a BS20 for fallback PUSCH transmissions provided by embodiments of the present application in some embodiments. The UE10 may include a processor 11, a memory 12, and a transceiver 13. The base station 20, e.g., generating a node b (gnb), may include a processor 21, a memory 22, and a transceiver 23. The

processor

11 or 21 may be configured to implement the proposed functions, processes and/or methods described in this specification. The layers of the radio interface protocol may be implemented in the

processor

11 or 21. The

memory

12 or 22 is operatively coupled with the

processor

11 or 21 and stores various information to operate the

processor

11 or 21. The

transceiver

13 or 23 is operatively coupled to the

processor

11 or 21, the

transceiver

13 or 23 transmitting and/or receiving radio signals.

The

processor

11 or 21 may comprise an application-specific integrated circuit (ASIC), other chipset, logic circuit and/or data processing device. The

memory

12 or 22 may include read-only memory (ROM), Random Access Memory (RAM), flash memory, memory cards, storage media, and/or other storage devices. The

transceiver

13 or 23 may include a baseband circuit that processes radio frequency signals. When an embodiment is implemented in software, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The modules may be stored in the

memory

12 or 22 and executed by the

processor

11 or 21. The

memory

12 or 22 may be implemented within the

processor

11 or 21 or external to the

processor

11 or 21, where those may be communicatively coupled to the

processor

11 or 21 via various means as is known in the art.

According to sidelink technology developed under 3GPP releases 14, 15, 16 and above, communication between UEs involves vehicle-to-outside (V2X) communication including vehicle-to-vehicle (V2V), vehicle-to-pedestrian (V2P), and vehicle-to-infrastructure/network (V2I/N). The UEs communicate directly with each other via a sidelink interface, such as a PC5 interface.

In some embodiments, the processor 11 is configured or indicated by the base station 20 with a first Tx beam and a second Tx beam, wherein the first Tx beam and the second Tx beam are configured for transmission over PUCCH. The processor 11 is configured to transmit the first Tx beam on a PUCCH resource in a first PUCCH resource group and the UE transmits the second Tx beam on a PUCCH resource in a second PUCCH resource group. The UE10 may determine the Tx beam for PUSCH transmission according to detecting an association between the PDCCH scheduling DCI, the first Tx beam, and the second Tx beam.

In some embodiments, the processor 11 is configured to divide PUCCH resources into a first PUCCH resource group and a second PUCCH resource group. In some embodiments, for PUSCH transmissions scheduled with a DCI format detected by the processor 11, the processor 11 further determines one of the first and second Tx beams to use according to a configuration of a PDCCH in which the DCI format is detected and an association between the PDCCH, the first Tx beam and the second Tx beam. In some embodiments, the DCI format comprises DCI format 0_ 0. In some embodiments, the processor 11 is further configured with a higher layer index associated with a configuration of a set of control resources, wherein the PUSCH transmission scheduled by the DCI format is performed by monitoring the PDCCH in a search space associated with the set of control resources, the method further comprising determining a spatial relationship of the PUSCH transmission according to a value of the higher layer index.

In some embodiments, the processor 11 is configured to use multiple PUCCH resources in a given uplink bandwidth portion of a cell, and each PUCCH resource is linked or configured with a PUCCH resource group identity. In some embodiments, the processor 11 is configured to configure a control resource set with a control resource set group identity and with an association between the PUCCH resource group identity and the control resource set group identity. In some embodiments, the set of control resources is associated with one or more PUCCH resources.

In some embodiments, the processor 11 is further configured with a slot aggregation configuration for PUSCH transmissions, wherein when the transceiver 13 receives a DCI format scheduling PUSCH transmissions, the processor 11 repeats the transport block across N consecutive slots according to the configuration of slot aggregation. In some embodiments, the processor 11 is indicated with a first PUCCH-spatial relationship information value and a second PUCCH-spatial relationship information value, the method further comprising determining to which of the first PUCCH-spatial relationship information value and the second PUCCH-spatial relationship information value the value of the higher layer index corresponds. In some embodiments, the first PUCCH-spatial relationship information value and the second PUCCH-spatial relationship information value each comprise a channel state information reference signal resource index, a sounding reference signal resource index, or a synchronization signal/physical broadcast channel block index.

Fig. 4 illustrates a method 400 of fallback PUSCH transmission for a UE according to an embodiment of the present application. The method 400 includes: the UE is configured or indicated by the BS with a first Tx beam and a second Tx beam configured for transmission over PUCCH, block 410, and the UE transmits the first Tx beam on PUCCH resources in a first PUCCH resource group and the UE transmits the second Tx beam on PUCCH resources in a second PUCCH resource group, block 420. The method 400 performed by the UE may determine a Tx beam for PUSCH transmission according to an association between a Physical Downlink Control Channel (PDCCH) that detects scheduling Downlink Control Information (DCI), the first Tx beam, and the second Tx beam.

In some embodiments, the method further comprises dividing PUCCH resources into a first PUCCH resource group and a second PUCCH resource group. In some embodiments, for PUSCH transmissions scheduled with a DCI format detected by the UE, the method further comprises determining one of the first and second Tx beams to use according to a configuration of a PDCCH and an association between the PDCCH, the first Tx beam and the second Tx beam in which the DCI format is detected. In some embodiments, the DCI format comprises DCI format 0_ 0. In some embodiments, the method further comprises being configured with a higher layer index associated with a configuration of a set of control resources, wherein the PUSCH transmission scheduled by the DCI format is performed by monitoring the PDCCH in a search space associated with the set of control resources, the method further comprising determining a spatial relationship of the PUSCH transmission according to a value of the higher layer index.

In some embodiments, the method further comprises being configured with a plurality of PUCCH resources in a given uplink bandwidth portion of the cell, and each PUCCH resource is linked or configured with a PUCCH resource group identity. In some embodiments, in the configuring of the control resource set, the method includes configuring one control resource set with one control resource set group identity and with an association between the PUCCH resource group identity and the control resource set group identity. In some embodiments, the set of control resources is associated with one or more PUCCH resources.

In some embodiments, the method further comprises configuring a slot aggregation configuration for the PUSCH transmission, wherein when the UE receives the DCI format scheduling the PUSCH transmission, the UE repeats the transport block across N consecutive slots according to the configuration of slot aggregation. In some embodiments, the method further comprises being indicated with a first PUCCH-spatial relationship information value and a second PUCCH-spatial relationship information value, the method further comprising determining which of the first PUCCH-spatial relationship information value and the second PUCCH-spatial relationship information value the value of the higher layer index corresponds to. In some embodiments, the first PUCCH-spatial relationship information value and the second PUCCH-spatial relationship information value each comprise a channel state information reference signal resource index, a sounding reference signal resource index, or a synchronization signal/physical broadcast channel block index.

Fig. 5 illustrates a method for determining a spatial relationship of a PUSCH transmission scheduled by a DCI format including DCI format 0_0 according to an embodiment of the present application.

In the example shown in fig. 1. Referring to fig. 5, in operation 510, a UE is configured with two CORESET. The first CORSET is associated with a high level index set to 0 and the second CORESET is associated with a high level index set to 1. In operation 520, the UE, the first and second spatial relationship _ info, may be indicated with two spatial relationship _ info values for the PUCCH resource in a given BWP. The UE may be requested to apply the first spatial relationship information to transmissions of a subset of PUCCH resources in a given BWP and may be requested to apply the second spatial relationship information to transmissions of other PUCCH resources in the given BWP. In operation 530, the UE may detect one DCI format 0_0 in the PDCCH and DCI format 0_0 schedules PUSCH transmission. Then, in operation 540, the UE may determine a value of a higher layer index associated with the core set in which the DCI format 0_0 is detected. In other words, the UE may determine the value of the higher layer index associated with the CORESET associated with the search space in which DCI format 0_0 was detected. In operation 550, the UE may determine whether the value of the higher layer index is 0 or 1. In other words, if the higher layer index associated with the CORESET is set to 0, for that PUSCH scheduled by DCI format 0_0, the UE may transmit the PUSCH according to the spatial relationship corresponding to the indicated first spatial relationship _ info in operation 560. On the other hand, if the higher layer index associated with the CORESET is set to 1, for the PUSCH scheduled by the DCI format 0_0, the UE may transmit the PUSCH according to the spatial relationship corresponding to the indicated first spatial relationship _ info in operation 570.

In some embodiments of the present application, a transmission method of PUSCH scheduled by DCI format 0_0 is proposed. In some embodiments, the beams may correspond to RS resources, which may be CSI-RS resources, SRS resources, SS/PBCH blocks, or any other type of RS.

In one embodiment, the UE may be configured or instructed with two Tx beams, a first Tx beam and a second Tx beam, for uplink PUCCH transmission. The UE may divide the UE-specific configured PUCCH resources into two groups, a first PUCCH resource group and a second PUCCH resource group. The UE may apply the first Tx beam for transmission on a PUCCH resource in the first set of PUCCH resources and apply the second Tx beam for transmission on a PUCCH resource in the second set of PUCCH resources. For DCI format 0_0 scheduled transmission of PUSCH, the UE may determine which of the first Tx beam or the second Tx beam may be used according to the configuration of the PDCCH that detects DCI format 0_0 and the association between the PDCCH and the Tx beam indicated for the PUCCH resource.

In one approach, a UE may be configured with a first higher layer index associated with a configuration of a first control resource set (CORESET). For a PUCCH resource in a given UL BWP in one cell, the UE may be indicated with two PUCCH-SpatialRelationInfo values, a first PUCCH-SpatialRelationInfo value and a second PUCCH-SpatialRelationInfo value. In one example, the PUCCH-SpatialRelationInfo value may be signaled by higher layer signaling, such as a MAC CE message or an RRC message. For a PUSCH transmission scheduled by DCI format 0_0, which is detected by monitoring the PDCCH in the search space associated with the first CORESET, the UE may determine the spatial relationship of the transmission on this PUSCH from the value of the higher layer index associated with the configuration of the first CORESET.

In some embodiments, if the first higher layer index associated with the configuration of the first set is set to, e.g., 0, the UE may send the PUSCH transmission according to the spatial relationship corresponding to the first PUCCH-spatial relationship info value indicated for the PUCCH resources in a given UL BWP. In some embodiments, if a first higher layer index associated with the configuration of the first set is set, e.g., 1, the UE may send the PUSCH transmission according to a spatial relationship corresponding to a second PUCCH-spatial relationinfo value indicated for the PUCCH resource in a given UL BWP. In some embodiments, each PUCCH-SpatialRelationInfo value contains one CSI-RS resource index or one SRS resource index or one SS/PBCH block index. For DCI format 0_0 scheduled transmission of PUSCH, if the corresponding PUCCH-spatial relationship info value used by the UE contains one CSI-RS resource or one SS/PBCH block, the UE may use the same spatial domain transmit filter as the spatial domain receive filter used to receive the CSI-RS resource or SS/PBCH block. In some embodiments, if the corresponding PUCCH-SpatialRelationInfo value used by the UE contains one SRS resource, the UE may use the same spatial-domain transmit filter as used to transmit the SRS resource.

In one approach, a UE may be configured with multiple PUCCH resources in a given UL bandwidth part (BWP) in a cell. And these PUCCH resources may be configured in two PUCCH resource groups, and each PUCCH resource may be linked or configured with a PUCCH resource group ID. In the configuration of the core set, a core set group ID of one core may be configured for the UE. The UE may configure an association between the PUCCH resource group ID and the sets group ID. For each PUCCH resource group, the UE may be indicated or notified with one PUCCH spatial relationship _ info value, and may be requested to transmit any PUCCH resource in the PUCCH resource group according to a spatial relationship corresponding to the PUCCH spatial relationship _ info value configured or indicated for the group. In some embodiments, for a PUSCH scheduled by DCI format 0_0, the UE may be requested to transmit the PUSCH according to a spatial relationship corresponding to a PUCCH spatial relationship _ info value configured or indicated for a PUCCH group having a PUCCH group ID associated with a CORESET group ID of the CORESET that detected DCI format 0_ 0.

In one approach, a UE may be configured with CORSET and CORSET is associated with one or more PUCCH resources. For the PUSCH scheduled by DCI format 0_0 detected in the CORESET, the UE may be requested to transmit the PUSCH according to a spatial relationship corresponding to PUCCH spatialrelationship _ info configured to the PUCCH resource having the lowest ID among PUCCH resources. The PUCCH resource is associated with the CORESET that detects DCI format 0_ 0.

As described in 3GPP release 15, for PUSCH transmissions, a UE may configure a slot aggregation factor to indicate slot level repetition of one PUSCH transmission. The timeslot aggregation timeslot factor may take a value of 2, 4, or 8. When the UE receives one DCI format 0_0 scheduling PUSCH transmission in slot N, the UE will repeat the same transport block in N consecutive slots, applying the same time domain symbol allocation in each slot.

In one embodiment, the UE may be configured with slot aggregation for PUSCH transmission and the UE may be configured/indicated with two Tx beams, a first Tx beam and a second Tx beam, for uplink PUCCH transmission in BWP in a cell. The UE may explicitly or implicitly divide the PUCCH resources configured in the BWP into two groups, may apply a first Tx beam to transmission of PUCCH resources among those PUCCH resources in the first PUCCH group, and may apply a second Tx beam to transmission of PUCCH resources among those PUCCH resources in the second PUCCH resource group. When the UE receives DCI format 0_0 scheduling PUSCH transmissions, the UE may repeat the transport block over N consecutive slots according to the slot aggregation configuration of the PUSCH transmission and may request the UE to apply a spatial relationship on these PUSCH transmissions according to one or more of the following. The UE may configure one CORESET and the CORESET is associated with one higher level index (e.g., called CORESET group ID). When the UE detects one DCI format 0_0 in the CORESET, the UE may repeatedly apply one spatial relationship to all transport blocks, the spatial relationship corresponding to the first Tx beam or the second Tx beam based on a value of a higher layer index associated with the CORESET in which DCI format 0_0 is detected. For example, if the value of the higher layer index is 0, the UE selects a first Tx beam, and if the value of the higher layer index is 1, the UE selects a second Tx beam. The UE may alternately apply the first Tx beam and the second Tx beam on the transport block repetition according to some configuration or predefined pattern. For example, the UE may configure the slot aggregation factor to be equal to 4. The UE receives one DCI lattice 0_0 at slot n, which schedules PUSCH transmission starting from slot n + m. The UE may then transmit PUSCH in slots n + m, n + m +1, n + m +2, and n + m + 3. For such PUSCH transmissions, the UE may be requested or configured to apply a first Tx beam on the PUSCH in slot n + m, a second Tx beam on the PUSCH in slot n + m +1, a first Tx beam on the PUSCH in slot n + m +2, and a second Tx beam on the PUSCH in slot n + m + 3.

In one approach, the UE may be configured with a higher layer index associated with the configuration of CORESET. For a PUCCH resource in a given UL BWP in one cell, the UE may be indicated with two PUCCH-SpatialRelationInfo values, a first PUCCH-SpatialRelationInfo value and a second PUCCH-SpatialRelationInfo value. In one example, the PUCCH-SpatialRelationInfo value may be signaled through higher layer signaling, e.g., a MACCE message or an RRC message. For PUSCH transmission, a UE may be configured with one or more of the following. A PUSCH slot aggregation factor, which may be used to indicate how many slots (or subslots) the same PUSCH may be repeated. 2. PUSCH spatial relationship pattern for PUSCH repetition. One example of this parameter is a bitmap to indicate which Tx beam can be applied for one transport block transmission. For example, a bitmap a1a2 … a8, and each bit in the bitmap may indicate which one of PUCCH-SpatialRelationInfo values may be applied to a corresponding PUSCH repetition. For example, ai equal to 0 may indicate a first PUCCH-SpatialRelationInfo value, and ai equal to 1 may indicate a second PUCCH-SpatialRelationInfo value.

In some embodiments, for a transmission of a PUSCH scheduled by DCI format 0_0, the UE may determine the spatial relationship for each transmission occasion to apply to the transport block of that PUSCH based on one or more of the following factors. 1. DCI format 0_0 is detected by a high-level index value configured to CORESET. 2. Association between a higher layer index value configured to the set and a PUCCH group, or a spatial _ info value indicated for the PUCCH in a given BWP. 3. Configured PUSCH aggregation factor. 4. Configured PUSCH spatial relationship pattern.

In one method, if DCI format 0_0 is detected in core set whose configured higher layer index value implicitly or explicitly corresponds to the first PUCCH-SpatialRelationInfo value, the UE may be requested to apply a spatial relationship at each transmission occasion of a transport block as follows. 1. In the configured PUSCH spatial relationship mode, if a is equal to 0, the UE may apply a spatial relationship corresponding to the first PUCCH-SpatialRelationInfo at the nth transmission opportunity of the TB. 2. In the configured PUSCH spatial relationship mode, if an is equal to 1, the UE may apply a spatial relationship corresponding to the second PUCCH-spatial relationship info at the nth transmission occasion of the transport block.

In one method, if DCI format 0_0 is detected in core set where a value of a configured higher layer index implicitly or explicitly corresponds to a second PUCCH-SpatialRelationInfo value, the UE may be requested to apply a spatial relationship at each transmission occasion of a transport block as follows. 1. In the configured PUSCH spatial relationship mode, if a is equal to 0, the UE may apply a spatial relationship corresponding to the second PUCCH-spatialrelalationinfo at the nth transmission occasion of the transport block. In the configured PUSCH spatial relationship mode, if a is equal to 1, the UE may apply a spatial relationship corresponding to the first PUCCH-spatialrelalationinfo at the nth transmission occasion of the transport block.

In one approach, if DCI format 0_0 is detected in CORESET that does not configure a higher layer index, the UE may be requested to apply a spatial relationship at each transmission occasion of a transport block as follows. 1. In the configured PUSCH spatial relationship mode, if an is equal to 0, the UE may apply a spatial relationship corresponding to the first PUCCH-spatial relationship info at the nth transmission occasion of the transport block. 2. In the configured PUSCH spatial relationship mode, if an is equal to 1, the UE may apply a spatial relationship corresponding to the second PUCCH-spatial relationship info at the nth transmission occasion of the transport block.

In summary, in some embodiments of the present application, methods are proposed for a UE to determine spatial relationship information for transmission of PUSCH scheduled by DCI format 0_ 0. For all PUCCH resources configured in one given BWP, the PUCCH resources may be explicitly or implicitly divided into two groups. For one of such groups, the gNB may indicate one spatial _ info that applies to all PUCCH resources contained in the group. For PUSCH scheduled by DCI format 0_0, the UE may determine the spatial relationship of this PUSCH transmission based on the value of the higher layer index configured for the PDCCH that detected DCI format 0_0 and the spatial relationship _ info indication of the association between the higher layer index and the PUCCH group.

According to some embodiments of the present application, in a multi-TRP system, each TRP may flexibly and dynamically schedule PUSCH transmissions to a UE using DCI format 0_ 0. For different TRP reception, the UE may apply different appropriate Tx beams on the PUSCH transmission accordingly. . When switching PUSCH reception and scheduling TRP, high layer signaling configuration and reconfiguration are not needed. Accordingly, the methods presented in some embodiments of the present application may provide low overhead and low delay signaling for supporting DCI 0_0 based PUSCH transmission in a multi-TRP system.

In an embodiment of the present application, a UE and a method for fallback PUSCH transmission can provide high reliability, low overhead, and low delay signaling for supporting a DCI format to support DCI format based PUSCH transmission in a TRP system. Each TRP may schedule PUSCH transmissions for a UE, and the UE may apply a different Tx beam accordingly. Embodiments of the present application are a combination of techniques/processes that may be employed in 3GPP specifications to create an end product.

Fig. 6 is a block diagram of an example system 700 for wireless communication in accordance with an embodiment of the present application. The embodiments described herein may be implemented into a system using any suitably configured hardware and/or software. Fig. 6 shows a system 700, the system 700 including Radio Frequency (RF) circuitry 710, baseband circuitry 720, application circuitry 730, memory/storage 740, a display 750, a camera 760, sensors 770, and an input/output (I/O) interface 780, coupled to each other at least as shown.

The application circuitry 730 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor may include any combination of general-purpose processors and special-purpose processors (e.g., a graphics processor and an application processor). The processor may be coupled with the memory/storage and configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems to run on the system.

Baseband circuitry 720 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor may comprise a baseband processor. The baseband circuitry may handle various wireless control functions that enable communication with one or more wireless networks via the RF circuitry. The wireless control functions may include, but are not limited to, signal modulation, encoding, decoding, radio frequency shifting, and the like. In some embodiments, the baseband circuitry may provide communications compatible with one or more wireless technologies. For example, in some embodiments, the baseband circuitry may support communication with Evolved Universal Terrestrial Radio Access Network (EUTRAN) and/or other Wireless Metropolitan Area Networks (WMAN), Wireless Local Area Networks (WLANs), Wireless Personal Area Networks (WPANs). Embodiments in which the baseband circuitry is configured to support wireless communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry. In various embodiments, baseband circuitry 720 may include circuitry for operating with signals that are not strictly considered to be in baseband frequencies. For example, in some embodiments, the baseband circuitry may include circuitry for operating with signals having an intermediate frequency between the baseband frequency and the radio frequency.

RF circuitry 710 may use the modulated electromagnetic radiation to enable communication with a wireless network through a non-solid medium. In various embodiments, the RF circuitry may include switches, filters, amplifiers, and the like to facilitate communication with the wireless network. In various embodiments, RF circuitry 710 may include circuitry for operating with signals that are not strictly considered to be at radio frequencies. For example, in some embodiments, the baseband circuitry may include circuitry for operating with signals having an intermediate frequency between the baseband frequency and the radio frequency.

In various embodiments, the transmitter circuitry, control circuitry, or receiver circuitry discussed above with respect to the user equipment, eNB, or gNB may be implemented in whole or in part in one or more of RF circuitry, baseband circuitry, and/or application circuitry. As used herein, "circuitry" may refer to, or include, portions of: an Application Specific Integrated Circuit (ASIC), an electronic circuit executing one or more software or firmware programs, a processor (shared, dedicated, or group) and/or memory (shared, dedicated, or group), a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some embodiments, the electronics circuitry may be implemented by, or functions associated with, one or more software or firmware modules. In some embodiments, some or all of the constituent components of the baseband circuitry, application circuitry, and/or memory/storage devices may be implemented together on a system on a chip (SOC).

Memory/storage 740 may be used to load and store data and/or instructions, for example, for a system. The memory/storage of one embodiment may comprise any combination of suitable volatile memory (e.g., Dynamic Random Access Memory (DRAM)) and/or non-volatile memory (e.g., flash memory). In various embodiments, the I/O interface 780 may include one or more user interfaces designed to enable a user to interact with the system and/or a peripheral component interface designed to enable a peripheral component to interact with the system. The user interface may include, but is not limited to, a physical keyboard or keypad, a touchpad, a speaker, a microphone, and the like. The peripheral component interfaces may include, but are not limited to, a non-volatile memory port, a Universal Serial Bus (USB) port, an audio jack, and a power interface.

In various embodiments, the sensor 770 may include one or more sensing devices for determining environmental conditions and/or location information related to the system. In some embodiments, the sensors may include, but are not limited to, a gyroscope sensor, an accelerometer, a proximity sensor, an ambient light sensor, and a positioning unit. The positioning unit may also be part of or interact with baseband circuitry and/or RF circuitry to communicate with components of a positioning network, such as Global Positioning System (GPS) satellites. In various embodiments, display 750 may include displays such as liquid crystal displays and touch screen displays. In various embodiments, system 700 may be a mobile computing device, such as, but not limited to, a laptop computing device, a tablet computing device, a netbook, an ultrabook, a smartphone, and the like. In various embodiments, the system may have more or fewer components and/or different architectures. Where appropriate, the methods described herein may be implemented as a computer program. The computer program may be stored on a storage medium, such as a non-transitory storage medium.

It will be understood by those of ordinary skill in the art that each of the units, algorithms, and steps described and disclosed in the embodiments of the present application are implemented using electronic hardware or a combination of software and electronic hardware for a computer. Whether these functions are executed by hardware or software depends on the application conditions and design requirements of the technical solution. Those of ordinary skill in the art may implement the functionality of each particular application in a variety of ways, and such implementation decisions should not be interpreted as causing a departure from the scope of the present application. It will be appreciated by persons skilled in the art that, since the operation of the above-described systems, devices and units is substantially the same, reference may be made to the operation of the systems, devices and units in the above-described embodiments. For convenience of description and brevity, these operations will not be described in detail.

It should be understood that the systems, devices, and methods disclosed in the embodiments of the present application may be implemented in other ways. The above embodiments are merely illustrative. The division of the cells is based on logic functions only, and other division modes can be provided in practice. Multiple units or components may be combined or may be integrated into another system. Some features may be omitted or skipped. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The elements described as separate components may or may not be physically separate. The unit for displaying may or may not be a physical unit, i.e. may be located in one place, or may also be distributed over a plurality of network units. Some or all of the units may be used according to the purpose of the embodiments. In addition, functional units in the embodiments may be integrated into one processing unit, may be physically independent, or may be integrated into one processing unit by two or more units.

If the software functional units are implemented and sold or used as a stand-alone product, they may be stored in a computer readable storage medium. Based on such understanding, the technical solutions proposed by the present disclosure can be implemented in the form of software products in nature or in part. Or a part of the technical solution that contributes to the prior art, may be implemented in the form of a software product. The software product in the computer is stored in a storage medium and includes a plurality of commands for a computing device (e.g., a personal computer, server, or network device) to execute all or part of the steps disclosed in the embodiments of the present disclosure. The storage medium includes a USB disk, a removable hard disk, a ROM, a RAM, a floppy disk, or other medium capable of storing program codes.

While the disclosure has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the disclosure is not to be limited to the disclosed embodiment, but is intended to cover various arrangements made without departing from the broadest interpretation of the appended claims.

Claims

1. A method for fallback physical uplink shared channel transmission of a user equipment, comprising:

the user equipment is configured or indicated by a base station with a first transmission beam and a second transmission beam, wherein the first transmission beam and the second transmission beam are configured for transmission through a physical uplink control channel; and

and the user equipment sends the first transmission beam on a physical uplink control channel resource in a first physical uplink control channel resource group and sends the second transmission beam on a physical uplink control channel resource in a second physical uplink control channel resource group.

2. The method of claim 1, wherein for a physical uplink shared channel transmission scheduled by a downlink control information format detected by the user equipment, the method further comprises determining one of the first transmission beam and the second transmission beam to be used according to a configuration of a physical downlink control channel and an association between the physical downlink control channel, the first transmission beam and the second transmission beam, wherein the downlink control information format is detected in the physical downlink control channel.

3. The method of claim 2, wherein the downlink control information format comprises a downlink control information format 0_ 0.

4. The method of claim 2, further comprising configuring a higher layer index associated with a configuration of a set of control resources, wherein the physical uplink shared channel transmission scheduled by the downlink control information format is performed by steering the physical downlink control channel in a search space associated with the set of control resources, and further comprising determining a spatial relationship of the physical uplink shared channel transmission according to a value of the higher layer index.

5. The method of claim 4, further comprising being configured with a plurality of physical uplink control channel resources in a given uplink bandwidth portion of a cell, and wherein each physical uplink control channel resource is linked or configured with a physical uplink control channel resource group identity.

6. The method of claim 5, wherein the configuration of the control resource set comprises configuring a control resource set with a control resource set group id and configuring an association between the physical uplink control channel resource group id and the control resource set group id.

7. The method of claim 4, wherein the set of control resources is associated with one or more physical uplink control channel resources.

8. The method according to claim 4, wherein the method further comprises being indicated with a first physical uplink control channel-spatial relationship information value and a second physical uplink control channel-spatial relationship information value, the method further comprising determining which of the first physical uplink control channel-spatial relationship information value and the second physical uplink control channel-spatial relationship information value the value of the higher layer index corresponds to.

9. The method of claim 1, wherein the first physical uplink control channel-spatial relationship information value and the second physical uplink control channel-spatial relationship information value each comprise a channel state information reference signal resource index, a sounding reference signal resource index, or a synchronization signal/physical broadcast channel block index.

10. A user equipment for fallback to a physical uplink shared channel transmission, comprising:

a memory;

a transceiver; and

a processor coupled to the memory and the transceiver;

wherein the processor is to:

configured or indicated by a base station with a first transmit beam and a second transmit beam, wherein the first transmit beam and the second transmit beam are configured for transmission over a physical uplink control channel; and

and transmitting the first transmission beam on a physical uplink control channel resource in a first physical uplink control channel resource group and transmitting the second transmission beam on a physical uplink control channel resource in a second physical uplink control channel resource group.

11. The UE of claim 10, wherein for a physical uplink shared channel transmission scheduled by a downlink control information format detected by the UE, the method further comprises determining one of the first and second transmission beams to be used according to a configuration of a physical downlink control channel in which the downlink control information format is detected and an association between the physical downlink control channel, the first transmission beam, and the second transmission beam.

12. The UE of claim 11, wherein the downlink control information format comprises a downlink control information format 0_ 0.

13. The UE of claim 11, wherein the processor is further configured with a higher layer index associated with a configuration of a control resource set, wherein the PDCCH transmission scheduled by the PDCCH is monitored in a search space associated with the control resource set, and wherein the method further comprises determining a spatial relationship of the PDCCH transmission according to a value of the higher layer index.

14. The UE of claim 13, wherein the processor is configured with a plurality of physical uplink control channel resources in a given uplink bandwidth portion of a cell, and wherein each physical uplink control channel resource is linked or configured with a physical uplink control channel resource group ID.

15. The UE of claim 14, wherein in the configuring of the control resource set, the processor is configured with a control resource set group ID for a control resource set and with an association between the PUCCH resource group ID and the control resource set group ID.

16. The UE of claim 13, wherein the set of control resources is associated with one or more physical uplink control channel resources.

17. The UE of claim 13, wherein the processor is further instructed with a first PUCCH-spatial relationship information value and a second PUCCH-spatial relationship information value, and wherein the processor further determines which of the first PUCCH-spatial relationship information value and the second PUCCH-spatial relationship information value the value of the higher layer index corresponds to.

18. The UE of claim 10, wherein the first PUCCH-spatial relationship information value and the second PUCCH-spatial relationship information value each comprise a CSI-RS resource index, a SRS resource index, or a synchronization signal/PDCCH block index.

19. A non-transitory machine-readable storage medium having instructions stored thereon, wherein the instructions, when executed by a computer, cause the computer to perform the method of any of claims 1 to 9.

20. A chip, comprising:

a processor configured to call and run a computer program stored in a memory to cause a device in which the chip is installed to perform the method of any one of claims 1 to 9.

21. A computer-readable storage medium, characterized in that a computer program is stored, wherein the computer program causes a computer to perform the method according to any one of claims 1 to 9.

22. A computer program product, comprising a computer program, wherein the computer program causes a computer to perform the method according to any one of claims 1 to 9.

23. A computer program, characterized in that the computer program causes a computer to perform the method according to any one of claims 1 to 9.