WO2022027557A1

WO2022027557A1 - Mbms feedback processing method, base station, and user equipment

Info

Publication number: WO2022027557A1
Application number: PCT/CN2020/107712
Authority: WO
Inventors: Xin Zhang; Jia SHENG
Original assignee: JRD Communication (Shenzhen) Ltd.
Priority date: 2020-08-07
Filing date: 2020-08-07
Publication date: 2022-02-10
Also published as: CN116615877A

Abstract

A media broadcast and multicast service (MBMS) feedback processing method is executed by a user equipment (UE) and a base station (BS). The BS provides feedback mechanism for MBMS in response to a request from the UE. The disclosed method also provides establishment of an MBMS UL feedback channel as a new establishment cause in a random access procedure initiated by an idle UE, or as a new resume cause in a random access procedure initiated by an inactive UE. The BS may send MBMS configuration indication to the UE, including feedback resource indication allocating radio resources for the feedback channel. The MBMS configuration indication may include other HARQ related information, such as HARQ process identifier (ID), and redundancy version (RV).

Description

MBMS FEEDBACK PROCESSING METHOD, BASE STATION, AND USER EQUIPMENT

Technical Field

The present disclosure relates to the field of communication systems, and more particularly, to MBMS feedback processing method, base station, and user equipment.

Background Art

Wireless communication systems, such as the third-generation (3G) of mobile telephone standards and technology are well known. Such 3G standards and technology have been developed by the Third Generation Partnership Project (3GPP) . The 3rd generation of wireless communications has generally been developed to support macro-cell mobile phone communications. Communication systems and networks have developed towards being a broadband and mobile system. In cellular wireless communication systems, user equipment (UE) is connected by a wireless link to a radio access network (RAN) . The RAN comprises a set of base stations (BSs) which provide wireless links to the UEs located in cells covered by the base station, and an interface to a core network (CN) which provides overall network control. As will be appreciated the RAN and CN each conduct respective functions in relation to the overall network. The 3rd Generation Partnership Project has developed the so-called Long Term Evolution (LTE) system, namely, an Evolved Universal Mobile Telecommunication System Territorial Radio Access Network, (E-UTRAN) , for a mobile access network where one or more macro-cells are supported by a base station known as an eNodeB or eNB (evolved NodeB) . More recently, LTE is evolving further towards the so-called 5G or NR (new radio) systems where one or more cells are supported by a base station known as a gNB.

Technical Problem

Media broadcast and multicast service (MBMS) is downlink only in LTE. No feedback mechanism is available for MBMS. MBMS are currently absent in NR.

Technical Solution

A first aspect of the disclosure provides an MBMS feedback processing method executable in a UE. The method comprises:

transmitting a request for establishment of a feedback channel for multimedia broadcast multicast services (MBMS) transmission through a random access procedure; and

transmitting a feedback signal of the MBMS transmission through the feedback channel.

In particular, the feedback channel may be a new defined uplink channel dedicated to MBMS or a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) .

A second aspect of the disclosure provides an MBMS feedback processing method executable in a base station. The method comprises:

receiving a request for establishment of a feedback channel for multimedia broadcast multicast services (MBMS) transmission through a random access procedure; and

receiving a feedback signal of the MBMS transmission through the feedback channel.

A third aspect of the disclosure provides a user equipment comprising a transceiver and a processor connected with the transceiver. The processor is configured to execute the following steps comprising:

A fourth aspect of the disclosure provides a base station comprising a transceiver and a processor connected with the transceiver. The processor is configured to execute the following steps comprising:

The disclosed method may be implemented in a chip. The chip may include 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 execute the disclosed method.

The disclosed method may be programmed as computer executable instructions stored in non-transitory computer readable medium. The non-transitory computer readable medium, when loaded to a computer, directs a processor of the computer to execute the disclosed method.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory.

The disclosed method may be programmed as computer program product, that causes a computer to execute the disclosed method.

The disclosed method may be programmed as computer program, that causes a computer to execute the disclosed method.

Advantageous Effects

The disclosed method provides feedback mechanism for MBMS. The network may use feedback signals to perform MBMS retransmission and improve reliability. The disclosed method also provides establishment of an MBMS UL feedback channel as a new establishment cause in a random access procedure initiated by an idle UE. The disclosed method also provides establishment of an MBMS UL feedback channel as a new resume cause in a random access procedure initiated by an inactive UE.

Description of Drawings

In order to more clearly illustrate the embodiments of the present disclosure or related art, the following figures will be described in the embodiments are briefly introduced. It is obvious that the drawings are merely some embodiments of the present disclosure, a person having ordinary skill in this field can obtain other figures according to these figures without paying the premise.

FIG. 1 is a schematic diagram showing a telecommunication system.

FIG. 2 is a schematic diagram showing a disclosed method at a base station side according to an embodiment of the present disclosure.

FIG. 3 is a schematic diagram showing a disclosed method at a user equipment (UE) side according to an embodiment of the present disclosure.

FIG. 4 is a schematic diagram showing a disclosed method at a base station side according to another embodiment of the present disclosure.

FIG. 5 is a schematic diagram showing a disclosed method at a UE side according to another embodiment of the present disclosure.

FIG. 6 is a schematic diagram showing a 4-step random access procedure according to an embodiment of the present disclosure.

FIG. 7 is a schematic diagram showing a 2-step random access procedure according to an embodiment of the present disclosure.

FIG. 8 is a schematic diagram showing a 4-step random access procedure according to an embodiment of the present disclosure.

FIG. 9 is a schematic diagram showing a 2-step random access procedure according to an embodiment of the present disclosure.

FIG. 10 is a schematic diagram showing a 4-step random access procedure according to an embodiment of the present disclosure.

FIG. 11 is a schematic diagram showing a 2-step random access procedure according to an embodiment of the present disclosure.

FIG. 12 is a schematic diagram showing a disclosed method at a base station side according to an embodiment of the present disclosure.

FIG. 13 is a schematic diagram showing a disclosed method at a user equipment (UE) side according to an embodiment of the present disclosure.

FIG. 14 is a schematic diagram of a system for wireless communication according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the disclosure are described in detail with the technical matters, structural features, achieved objects, and effects with reference to the accompanying drawings as follows. Specifically, the terminologies in the embodiments of the present disclosure are merely for describing the purpose of the certain embodiment, but not to limit the disclosure.

The disclosed method provides feedback mechanism for MBMS. With reference to FIG. 1, a telecommunication system including a UE 10a, a UE 10b, a base station (BS) 200a, and a network entity device 300 may executes one or more embodiments of the disclosed method according to the present disclosure. FIG. 1 is shown for illustrative not limiting, and the system may comprise more UEs, BSs, and CN entities. Connections between devices and device components are shown as lines and arrows in the FIGs. The UE 10a may include a processor 11a, a memory 12a, and a transceiver 13a. The UE 10b may include a processor 11b, a memory 12b, and a transceiver 13b. The base station 200a may include a processor 201a, a memory 202a, and a transceiver 203a. The network entity device 300 may include a processor 301, a memory 302, and a transceiver 303. Each of the

processors

11a, 11b, 201a, and 301 may be configured to implement proposed functions, procedures and/or methods described in the description. Layers of radio interface protocol may be implemented in the

processors

11a, 11b, 201a, and 301. Each of the

memory

12a, 12b, 202a, and 302 operatively stores a variety of program and information to operate a connected processor. Each of the

transceiver

13a, 13b, 203a, and 303 is operatively coupled with a connected processor, transmits and/or receives radio signals or wireline signals. The UE 10a may be in communication with the UE 10b through a sidelink. The base station 200a may be an eNB, a gNB, or one of other types of radio nodes, and may configure radio resources and MBSFN sub-areas for the UE 10a and UE 10b.

Each of the

processor

11a, 11b, 201a, and 301 may include an application-specific integrated circuits (ASICs) , other chipsets, logic circuits and/or data processing devices. Each of the

memory

12a, 12b, 202a, and 302 may include a read-only memory (ROM) , a random access memory (RAM) , a flash memory, a memory card, a storage medium and/or other storage devices. Each of the

transceiver

13a, 13b, 203a, and 303 may include baseband circuitry and radio frequency (RF) circuitry to process radio frequency signals. When the embodiments are implemented in software, the techniques described herein can be implemented with modules, procedures, functions, entities and so on, that perform the functions described herein. The modules can be stored in a memory and executed by the processors. The memory can be implemented within a processor or external to the processor, in which those can be communicatively coupled to the processor via various means are known in the art.

The network entity device 300 may be a node in a CN. CN may include LTE CN or 5G core (5GC) which includes user plane function (UPF) , session management function (SMF) , mobility management function (AMF) , unified data management (UDM) , policy control function (PCF) , control plane (CP) /user plane (UP) separation (CUPS) , authentication server (AUSF) , network slice selection function (NSSF) , and the network exposure function (NEF) .

With cross reference to FIG. 2 and FIG. 3, the base station executes an embodiment of the disclose method. The base station transmits MBMS transmission in units of MBMS frames, subframe, slots, or sub-slots to a group of UEs, including the UE 10a and UE 10b (block 210) . Each of the UEs in the group may receive the MBMS transmission. Operations in blocks 310-312 may apply to each of the UEs in the group. In particular, a UE, such as one of the UE 10a and UE 10b, receives the MBMS transmission from the base station (block 310) .

The UE triggers a random access procedure (RAP) and transmits a request for establishment of a feedback channel for the MBMS transmission through the random access procedure (block 311) . The base station processes the random access procedure and receives the request for establishment of the feedback channel for the MBMS transmission through a random access procedure (block 211) . The random access procedure may include a four-step random access procedure or a two-step random access procedure. The feedback channel may be a new defined uplink channel dedicated to the MBMS transmission or a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) .

The UE transmits a feedback signal of the MBMS transmission through the feedback channel (block 312) . The base station receives a feedback signal of the MBMS transmission through the feedback channel (block 212) and performs MBMS retransmission in response to the feedback signal (block 213) . The feedback signal may include a hybrid automatic repeat request (HARQ) feedback signal. In the description, HARQ-ACK represents HARQ feedback which may include acknowledgment (ACK) and negative-acknowledgment (NACK) . The term network (NW) include at least the base station 200a or both of the base station 200a and the network entity device 300. A downlink control information (DCI) format is sent from a BS, such as the BS 200a, to a UE, such as the UE 10a or the UE 10b.

The feedback signal associated with the MBMS transmission may be carried in a request during the random access procedure or in a feedback message allocated with radio resources indicated by feedback resource indication. Feedback resource indication includes one or more configuration parameters sent from a BS, such as the BS 200a, to a UE, such as the UE 10a or the UE 10b, to indicate radio resources allocated to transmission of feedback signals associated with the MBMS transmission. The request during the random access procedure may include an RRC setup request RRCSetupRequest or an RRC resume request. The UE in an RRC idle state sends an RRC setup request in the random access procedure to transit to an RRC connected state. The UE in an RRC inactive state sends an RRC resume request in the random access procedure to transit to an RRC connected state. The RRC resume request may include a shorten RRC resume request RRCResumeRequest and a full-length RRC resume request RRCResumeRequest1.

Fields in an RRCResumeRequest IEs include resumeCause, resumeIdentity, and resumeMAC-I. The resumeCause provides a resume cause for the RRC connection resume request as provided by upper layers or RRC. The network is not expected to reject an RRCResumeRequest due to unknown cause value being used by the UE. The resumeIdentity includes a UE identity to facilitate UE context retrieval at the base station receiving the RRC connection resume request. The resumeMAC-I is an authentication token to facilitate UE authentication at the base station. The 16 least significant bits of the MAC-I calculated using the AS security configuration as specified in TS 38.331 clause 5.3.13.3.

Fields in an RRCResumeRequest1-IEs include resumeCause, resumeIdentity, and resumeMAC-I. The resumeCause provides a resume cause for the RRCResumeRequest1 as provided by upper layers or RRC. A base station is not expected to reject an RRCResumeRequest1 due to unknown cause value being used by the UE. The resumeIdentity includes a UE identity to facilitate UE context retrieval at the base station receiving the RRC connection resume request RRCResumeRequest1. The resumeMAC-I is an authentication token to facilitate UE authentication at the base station. The 16 least significant bits of the MAC-I calculated using the AS security configuration as specified in TS 38.331 clause 5.3.13.3.

An RRCSetupRequest IE includes a field of establishmentCause and a field of ue-Identity. The establishmentCause provides the establishment cause for the RRCSetupRequest in accordance with the information received from upper layers. The ue-Identity includes UE identity included to facilitate contention resolution by lower layers.

With cross reference to FIG. 4 and FIG. 5, the base station executes another embodiment of the disclose method. The base station transmits MBMS transmission in units of MBMS frames, subframe, slots, or sub-slots to the group of UEs, including the UE 10a and UE 10b (block 210a) , and sends a control signal to trigger a random access procedure for establishing a feedback channel associated with the MBMS transmission (block 211a) . Each of the UEs in the group may receive the MBMS transmission and the control signal. Operations in blocks 310-312 may apply to each of the UEs in the group. In particular, a UE, such as one of the UE 10a and UE 10b, receives the MBMS transmission from the base station (block 310a) . The UE receives the control signal, and triggers a random access procedure for establishing a feedback channel associated with the MBMS transmission in response to the control signal (block 311a) . The random access procedure may include a four-step random access procedure or a two-step random access procedure. The control signal may be DCI, a RRC signal, or an MAC CE.

The UE transmits a feedback signal of the MBMS transmission through the feedback channel (block 312a) . The base station receives a feedback signal of the MBMS transmission through the feedback channel (block 212a) and performs MBMS retransmission in response to the feedback signal (block 213a) .

4-step RAP:

4-step RAP is detailed in the following. A random access RA procedure can take two distinct forms: contention-based random access (CBRA) and contention-free random access (CFRA) procedures.

In four-step CBRA, a UE, such as one of the UE 10a and 10b, execute a first step by randomly selecting an RA preamble from a pool of preambles shared with other UEs in a cell. The UE selects a preamble and transmits the preamble in a message Msg1. A base station, such as the BS 200a, performs a second step by transmitting a random access response Msg 2 to the UE. If multiple UEs select and transmit the same preamble in message Msg1, all those UEs decode content of the same random access response Msg2 and perform a third step by transmitting radio resource control (RRC) setup requests Msg3 on the same uplink (UL) time domain and frequency domain radio resources to the base station. In the fourth step (Msg4) , the base station resolves random access contention.

In CFRA, the UE uses a dedicated preamble provided by the network, such as the base station 200a, specifically to this UE via RRC signaling or a physical downlink control channel (PDCCH) signal.

The RA procedure may be initiated by a PDCCH signal from the base station, a medium access control (MAC) entity of the UE, or an RRC signal. The RA procedure may be triggered by a number of events including:

(1) Initial access from an RRC_IDLE state in CBRA scenario;

(2) RRC Connection Re-establishment procedure in CBRA scenario;

(3) Downlink (DL) data arrival during RRC_CONNECTED when UL synchronization status is "non-synchronised" , that is, Out-of-Sync in CBRA or CFRA scenario;

(4) UL data arrival during RRC_CONNECTED when UL synchronization status is "non-synchronised" , that is, Out-of-Sync in CBRA scenario;

(5) UL data arrival during RRC_CONNECTED when there are no PUCCH resources available for a scheduling request (SR) in CBRA scenario;

(6) SR failure in CBRA scenario;

(7) Request by RRC signaling upon synchronous reconfiguration, such as in a handover operation, in CBRA or CFRA scenario;

(8) Transition from RRC_INACTIVE in CBRA scenario;

(9) Establishing time alignment for a secondary time advance group (TAG) in CBRA or CFRA scenario;

(10) Request for on-demand system information (SI) in CBRA or CFRA scenario; and

(11) Beam failure recovery (BFR) in CBRA or CFRA scenario.

The 4 Steps in an RA procedure is detailed in the following.

Msg1: Random Access Preamble Transmission:

A MAC entity in the UE instructs a physical layer (PHY) entity in the UE to deliver physical random access channel (PRACH) transmission using a preamble index, PRACH occasion, and a radio network temporary identifier (RNTI) , such as random access radio network temporary identifier (RA-RNTI) if available.

RA-RNTI is used to address the UE on PDCCH and in turn used for decoding of a physical downlink shared channel (PDSCH) for the random access response (RAR) .

The MAC entity calculates RA_RNTI for BFR request. In CFRA C-RNTI is used for RAR. The RA-RNTI may be obtained through the calculation given below:

RA-RNTI= 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id

● s_id is the index of the first orthogonal frequency division multiplexing (OFDM) symbol of the specified PRACH, where 0 ≤s_id < 14.

● t_id is the index of the first slot of the specified PRACH in a system frame, where 0 ≤t_id < 80.

● f_id is the index of the specified PRACH in the frequency domain, where 0 ≤f_id < 8.

● ul_carrier_id is the UL carrier used for Msg1 transmission, where 0 for normal uplink (NUL) and 1 for supplemental uplink (SUL) carriers.

Msg2: Random Access Response:

Once the RA preamble is transmitted, the UE waits for the acknowledgement (ACK) from the base station in the form of random access response (RAR) , known as Msg2.

The UE monitors for the RAR by detecting a DCI format 1_0 with cyclic redundancy check (CRC) scrambled by RA-RNTI/C-RNTI within a window configured by ra-ResponseWindow.

When RA preamble was transmitted for BFR using CFRA, ra-ResponseWindow is picked from BeamFailureRecoveryConfig. Within the RAR window indicated by the ra-ResponseWindow, the UE monitors for RAR in a PDCCH addressed to the C-RNTI associated with the UE on a search space indicated by recoverySearchSpaceId of a special cell (SpCell) . Within the RAR window, if the UE receives the PDDCH addressed to C-RNTI associated with the UE, the UE recognizes the RA procedure as successfully completed.

In all other cases where an RA procedure is not triggered for BFR, the UE obtains ra-ResponseWindow from RACH-ConfigCommon. Within the RAR window, the UE monitors for RAR in PDCCH addressed to RA-RNTI associated with the UE.

If RAR is included in a MAC sub-protocol data unit (PDU) with random access preamble identifier (RAPID) equal to the preamble ID transmitted by the UE, the UE recognizes RAR reception is successful.

Except for the case where RA procedure is not initiated for “SI request” , the MAC RAR is included in the MAC subPDU and contains a timing advance command, UL grant, and a Temporary_C-RNTI.

Generally, the RA response from the network includes a RAPID, a timing advance command, a UL grant, and a temporary C-RNTI, which are detailed in the following:

● RAPID: random access preamble identifier detected by the network;

● Timing Advance Command: timing advance calculated by the network based on the received timing of the RA preamble;

● UL Grant: grant required for the UE’s subsequent UL transmission, such as Msg3;

● Temporary_C-RNTI: C-RNTI temporarily used for communication between UE and the base station for the rest of the RA procedure.

For a CFRA procedure, the UE upon receiving RA response, recognizes the RA procedure as successfully completed. For a CBRA procedure, the UE transmits Msg3 over PUSCH using the UL grant received in MAC RAR and proceeds to the next step of contention resolution.

If PDCCH addressed to RA-RNTI/C-RNTI associated with the UE is not received within RAR-Window, that is, when ra-ResponseWindow has expired, the UE recognizes the RAR reception as not successful and returns to “RA Resource Selection procedure” , and a preamble retransmission may be performed with higher transmit power.

Msg3:

For a CBRA procedure, the UE transmits Msg3 over PUSCH using UL grant received in the MAC RAR. The UE includes an identity in the Msg3 which is used later in the process of contention resolution. The UE uses Temporary_C-RNTI for the transmission of Msg3. Content of Msg3 varies depending on whether the UE already has a C-RNTI or not as discussed below.

A first case where UE already has a C-RNTI is detailed in the following.

The UE may already have a C-RNTI at the time of RA procedure initiation. For example, the UE is in an RRC_CONNECTED state. The applicable cases and the associated Msg3 contents are given below.

● - When the RA procedure is initiated for BFR, the UE sends C-RNTI MAC CE in Msg3.

● - When the RA procedure is initiated by a PDCCH signal, the UE sends C-RNTI MAC CE in Msg3. This case is CBRA if the network sets the preamble ID in PDCCH signal to 0b000000.

● - When the RA procedure was initiated by the MAC sublayer itself or by the RRC sublayer, the UE sends C-RNTI MAC CE in Msg3, and additionally, the following is applicable;

· In the case of CBRA during synchronous RRC reconfiguration, such as in a handover operation, the UE transmits an RRCReconfigurationComplete message in Msg3.

· When the UE needs to transmit uplink data and if SR is not configured or SR failure or uplink Out-of-Sync, the UE may also transmit a buffer status report (BSR) MAC CE to the base station to indicate buffer status and get appropriate uplink resources from the network.

A second case where UE does not have a C-RNTI is detailed in the following.

The UE sends a common control channel (CCCH) service data unit (SDU) in Msg3 when not having a C-RNTI at the time of initiation of RA procedure, such as during initial access. The applicable cases and the associated Msg3 content are detailed in the following.

● - When the UE is transitioning from RRC_IDLE to RRC_CONNECTED, the UE sends an RRC setup request message RRCSetupRequest in Msg3 through UL CCCH.

● - When the UE is transitioning from RRC_INACTIVE to RRC_CONNECTED, the UE sends an RRC resume request message RRCResumeRequest or RRCResumeRequest1 message in Msg3 through UL CCCH.

● - During an RRC connection re-establishment procedure, the UE sends an RRC connection re-establishment request message RRCReestablishmentRequest in Msg3 through UL CCCH.

● - When using CBRA for on-demand SI, the UE sends an RRC system information request message RRCSystemInfoRequest in Msg3 through UL CCCH.

Msg4: Contention Resolution

Once Msg3 is transmitted, the UE starts or restarts a timer ra-ContentionResolutionTimer and monitors PDCCH. The contention resolution procedure varies depending on whether or not UE had a C-RNTI during initiation of RA procedure.

Case 1: UE already had a C-RNTI

A first case where UE already has a C-RNTI is detailed in the following.

The UE, for example, in RRC_CONNECTED, may already have a C-RNTI during initiation of an RA procedure.

If the C-RNTI MAC CE is included in Msg3, the network resolves contention just by transmitting PDCCH addressed to the C-RNTI in an uplink grant or downlink assignment associated with the UE. The UE recognizes that the RA procedure is successfully completed and discards Temporary_C-RNTI. Note that the network need not to explicitly transmit contention resolution information in the downlink.

The UE recognizes the contention resolution as not successful if the UE doesn’t detect PDCCH addressed to C-RNTI during a timer window indicated by the ra-ContentionResolutionTimer.

Case 2: UE didn’t have a C-RNTI:

A second case where UE does not have a C-RNTI is detailed in the following.

When the UE doesn’t have a valid C-RNTI, the base station transmits a UE contention resolution identity MAC CE Msg4 using Temporary_C-RNTI to the UE.

The “UE Contention Resolution Identity” MAC CE is identified by MAC subheader with logical channel ID: 62, fixed 48-bit size and consists of single field “UE Contention Resolution Identity” . In this MAC CE, the base station replays first 48-bits of UL CCCH SDU received in Msg3.

If the received contention resolution identity matches with the transmitted identity, the UE recognizes the contention resolution and the RA procedure as successful.

In an SI request case where the RA procedure was initiated for on-demand SI, the MAC layer indicates the reception of an acknowledgement of an SI request to upper layers.

After contention resolution is successful, except for SI request case, the UE promotes the Temporary_C-RNTI to C-RNTI.

If not receiving contention resolution identity during a time window indicated by the ra-ContentionResolutionTimer, the UE recognizes that the contention resolution not successful.

2-step RAP:

The four-step random-access procedure requires two round-trip cycles between the UE and the base station, which not only increases the latency but also incurs additional control-signaling overhead. The motivation of two-step RACH is to reduce latency and control-signaling overhead by a single round trip cycle between the UE and the base station. This is achieved by combining the preamble (Msg1) and the scheduled PUSCH transmission (Msg3) into a single combined message MsgA from the UE, and by combining the random-access respond (Msg2) and the contention resolution message (Msg4) into a single message MsgB from the base station to UE.

All of the triggers for four-step RACH apply to two-step RACH including Msg3-based SI request and contention-based beam failure recovery (CB BFR) .

As previously described, MsgA consists of a PRACH preamble and a PUSCH transmission, known as MsgA PRACH and MsgA PUSCH respectively. The MsgA PRACH preambles are separated from the four-step RACH preambles, but can be transmitted in the same PRACH occasions (ROs) as the preambles of four-step RACH, or in separate ROs. The PUSCH transmissions are organized into PUSCH Occasions (POs) which span multiple symbols and physical radio blocks (PRBs) with optional guard periods and guard bands between consecutive POs. Each PO consists of multiple demodulation reference signal (DMRS) ports and DMRS sequences, with each DMRS port/DMRS sequence pair known as a PUSCH resource unit (PRU) . Two-step RACH supports at least one-to-one and multiple-to-one mapping between the preambles and PRUs.

After transmiting a MsgA, the UE waits for the MsgB response from the base station. The two-step RA procedure has three possible outcomes:

When the base station doesn’t detect the MsgA PRACH, no response is sent back to the UE. The UE retransmits MsgA or falls back to four-step RACH procedure starting with transmission of a Msg1.

When the base station detects MsgA preamble but fails to successful decode MsgA PUSCH, the base station sends back a fallbackRAR to the UE with the RAPID and an uplink grant for retransmission of the MsgA PUSCH. The UE upon receiving the fallbackRAR, falls back to four-step RACH procedure for transmission of Msg3 or retransmits the MsgA PUSCH.

When detecting MsgA and successfully decoding MsgA PUSCH, the base station sends back a successRAR to the UE with the contention resolution ID of MsgA. The UE receives the successRAR and successfully completes the two-step RACH procedure.

As previously described, a MsgB consists of the random-access response and the contention-resolution message. The random-access response is sent when the base station detects a preamble but cannot successfully decode the corresponding PUSCH transmission. The contention resolution message is sent after the base station successfully decodes the PUSCH transmission. The MsgB can contain backoff indication, fallbackRAR and/or successRAR. A single MsgB can contain the successRAR of one or more UEs. The fallbackRAR includes the RAPID, an uplink grant for retransmission of the MsgA PUSCH payload, and a time advance command. The successRAR includes at least the contention resolution ID, the C-RNTI and the TA command.

An embodiment of MBMS UL feedback triggered RACH procedure is detailed in the following.

MBMS UL feedback refer to as “MBMS-ULFB” in this disclosure is an event to trigger an RAP. The “MBMS-ULFB” is added in “cause” information elements (IEs) , such as “establimentcause” IE and “Resumecause” IE.

The disclosed method provides at least two options to carry HARQ-ACK bit.

In an embodiment, HARQ-ACK bits may be carried by the message Msg3 or Msg A. Allocation of feedback resource for the HARQ-ACK to the base station is not required by the message Msg3 and Msg A. Signalling overhead and latency associated with the HARQ-ACK for MBMS is reduced.

The message Msg3 and Msg A carrying HARQ-ACK bits may increase payload. The base station may limit a number of times for transmission or retransmission of HARQ-ACK bits carried by Msg3 or MsgA. The network may define a threshold indicating a number of times for transmission of HARQ-ACK carried by Msg3 or MsgA. For example, if the base station fails to receive or decode an initial transmission of Msg3 carrying HARQ-ACK, and the number of times for transmission of HARQ-ACK carried by Msg3 or MsgA is set to 1, the UE does not transmit another Msg3 or MsgA for retransmission of the HARQ-ACK.

Alternatively, HARQ-ACK bits may be carried by UL resources other than the message Msg3 or Msg A. When RAP completes successfully, UEs may transmit HARQ-ACK in allocated radio resources indicated by feedback resource indication.

Timing of RAP triggering:

The UE may determine when to trigger an RAP. For example, the UE may trigger an RAP when the UE need the RAP for HARQ feedback associated with the MBMS traffic. As previously detailed, HARQ feedback may be carried in a random access request, such as the Msg3 and MsgA. The HARQ feedback may include ACK and NACK. The UE may trigger the RAP and transmit HARQ-ACK upon receiving MBMS transmission.

In another embodiment, the UE may transmit NACK upon receiving MBMS transmission and failing to decode the MBMS transmission. The UE may trigger the RAP upon receiving MBMS transmission and failing to decode the MBMS transmission.

Alternatively, the UE may trigger an RAP when the UE need not the RAP for HARQ feedback associated with the MBMS traffic. If enabling of MBMS UL feedback is preconfigured for a cell or an MBMS area by the network, even though the RAP is not needed by the UE, the UE may automatically trigger the RAP upon entering the cell or the MBMS area of the MBMS transmission.

Retransmission of MBMS:

The NW may retransmit one unit, such as one transport block (TB) , a frame, a subframe, a slot, or a sub-slot, of the MBMS transmission upon receiving one NACK for the unit of MBMS transmission.

Alternatively, the NW may retransmit the unit of MBMS transmission upon receiving N NACKs for the unit of MBMS transmission during a window time, where the constant N is an positive integer and N＞1.

The Table 1 shows embodiments of the disclosed method for UEs in the idle state.

Table 1

Idle UE receiving MBMS service:

Embodiments of the disclosed method for idle UE is detailed in the following.

4-step: HARQ-ACK carried in Msg3:

With reference to FIG. 6, when the UE in an RRC idle state receives MBMS transmission, the UE triggers a 4-step random access procedure and adds “MBMS-ULFB” as “EstablishmentCause” into a message Msg3 to perform the 4-step random access procedure. HARQ-ACK for the MBMS transmission may be carried in the message Msg3, represented by the RRCSetupRequest.

With reference to FIG. 6, when attempting to transmit an HARQ feedback signal of the MBMS transmission, the UE in the RRC idle state transmits a random access preamble as the Msg 1 to the base station to trigger the RAP (block 611) . The base station receives the random access preamble and transmits a random access response as the Msg 2 to the UE in response to the Msg 1 (block 612) . The UE transmits an RRC setup request as the Msg3 to the base station in response to the Msg 2 (block 613) . The base station transmits a contention resolution message to the UE in response to the Msg3 (block 614) . The following table shows data structure of the RRCSetupRequest. An HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the four-step random access procedure.

Table 2

4-step: HARQ-ACK not carried in Msg3:

With reference to FIG. 6, when the UE in an RRC idle state receives MBMS transmission, the UE triggers a 4-step random access procedure and adds “MBMS-ULFB” as “EstablishmentCause” into a message Msg3 to perform the 4-step random access procedure. HARQ-ACK for the MBMS transmission is not carried in the message Msg3, represented by the RRCSetupRequest. The following table shows data structure of the RRCSetupRequest. An HARQ feedback bit for the MBMS transmission is not included as the feedback signal of the MBMS transmission in the RRC setup request in the four-step random access procedure.

Table 3

2-step: HARQ-ACK carried in MsgA:

With reference to FIG. 7, when the UE in an RRC idle state receives MBMS transmission, the UE triggers a 2-step random access procedure and adds “MBMS-ULFB” as “EstablishmentCause” into a message MsgA to perform the 2-step random access procedure. HARQ-ACK for the MBMS transmission is carried in the message MsgA, represented by a combined request including the RA preamble of the UE and the RRCSetupRequest.

With reference to FIG. 7, when attempting to transmit an HARQ feedback signal of the MBMS transmission, the UE in the RRC idle state transmits a combined request MsgA including a random access preamble and the RRCSetupRequest to the base station to trigger the RAP (block 711) . The base station receives the combined request MsgA and transmits a combined response as the MsgB including the RAR and the contention resolution message to the UE in response to the Msg A (block 712) . An HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRCSetupRequest in the 2-step random access procedure.

2-step: HARQ-ACK not carried in MsgA:

With reference to FIG. 7, when the UE in an RRC idle state receives MBMS transmission, the UE triggers a 2-step random access procedure and adds “MBMS-ULFB” as “EstablishmentCause” into a message MsgA to perform the 2-step random access procedure. HARQ-ACK for the MBMS transmission is not carried in the message MsgA, represented by a combined request including the RA preamble of the UE and the RRCSetupRequest. An HARQ feedback bit for the MBMS transmission is not included as the feedback signal of the MBMS transmission in the RRCSetupRequest in the 2-step random access procedure.

Inactive UE receiving MBMS service:

Embodiments of the disclosed method for inactive UE is detailed in the following.

The Table 4 shows embodiments of the disclosed method for UEs in the inactive state.

Table 4

4-step RAP and Msg3 with HARQ-ACK added in “RRCResumeRequest” :

With reference to FIG. 8, when the UE in an RRC inactive state receives MBMS transmission, the UE triggers a 4-step random access procedure and adds “MBMS-ULFB” as “ResumeCause” into a message Msg3 to perform the 4-step random access procedure. HARQ-ACK for the MBMS transmission is carried in the message Msg3, represented by the RRCResumeRequest. The RRCResumeRequest is a shorten RRC resume request comprising a ShortI-RNTI-Value as a UE identifier (UEID) .

With reference to FIG. 8, when attempting to transmit an HARQ feedback signal of the MBMS transmission, the UE in the RRC inactive state transmits a random access preamble as the Msg 1 to the base station to trigger the RAP (block 621) . The base station receives the random access preamble and transmits a random access response as the Msg 2 to the UE in response to the Msg 1 (block 622) . The UE transmits an RRC resume request RRCResumeRequest as the Msg3 to the base station in response to the Msg 2 (block 623) . The base station transmits a contention resolution message to the UE in response to the Msg3 (block 624) .

An HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the four-step random access procedure. The following table shows data structure of the RRCResumeRequest.

Table 5: RRCResumeRequest

Table 6: ResumeCause information element

4-step RAP and Msg3 with HARQ-ACK NOT added in “RRCResumeRequest” :

With reference to FIG. 8, when the UE in an RRC inactive state receives MBMS transmission, the UE triggers a 4-step random access procedure and adds “MBMS-ULFB” as “ResumeCause” into a message Msg3 to perform the 4-step random access procedure. HARQ-ACK for the MBMS transmission is not carried in the message Msg3, represented by the RRCResumeRequest. An HARQ feedback bit for the MBMS transmission is not included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the four-step random access procedure.

2-step RAP and MsgA with HARQ-ACK added in “RRCResumeRequest” :

With reference to FIG. 9, when the UE in an RRC inactive state receives MBMS transmission, the UE triggers a 2-step random access procedure and adds “MBMS-ULFB” as “ResumeCause” into a message MsgA to perform the 2-step random access procedure. HARQ-ACK for the MBMS transmission is carried in the message MsgA, represented by a combined request including the RA preamble of the UE and the RRCResumeRequest.

With reference to FIG. 9, when attempting to transmit an HARQ feedback signal of the MBMS transmission, the UE in the RRC inactive state transmits a combined request MsgA including a random access preamble and the RRCSetupRequest to the base station to trigger the RAP (block 721) . The base station receives the combined request MsgA and transmits a combined response as the MsgB including the RAR and the contention resolution message to the UE in response to the Msg A (block 722) . An HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRCSetupRequest in the 2-step random access procedure.

2-step RAP and MsgA with HARQ-ACK NOT added in “RRCResumeRequest” :

With reference to FIG. 9, when the UE in an RRC inactive state receives MBMS transmission, the UE triggers a 2-step random access procedure and adds “MBMS-ULFB” as “ResumeCause” into a message MsgA to perform the 2-step random access procedure. HARQ-ACK for the MBMS transmission is not carried in the message MsgA, represented by a combined request including the RA preamble of the UE and the RRCResumeRequest.

The Table 7 shows embodiments of the disclosed method for UEs in the inactive state.

Table 7

4-step RAP and Msg3 with HARQ-ACK added in “RRCResumeRequest1” :

With reference to FIG. 10, when the UE in an RRC inactive state receives MBMS transmission, the UE triggers a 4-step random access procedure and adds “MBMS-ULFB” as “ResumeCause” into a message Msg3 to perform the 4-step random access procedure. HARQ-ACK for the MBMS transmission is carried in the message Msg3, represented by an RRCResumeRequest1. The RRCResumeRequest1 is a full-length RRC resume request comprising a I-RNTI-Value as a UE identifier (UEID) .

With reference to FIG. 10, when attempting to transmit an HARQ feedback signal of the MBMS transmission, the UE in the RRC inactive state transmits a random access preamble as the Msg 1 to the base station to trigger the RAP (block 631) . The base station receives the random access preamble and transmits a random access response as the Msg 2 to the UE in response to the Msg 1 (block 632) . The UE transmits an RRC resume request RRCResumeRequest1 as the Msg3 to the base station in response to the Msg 2 (block 633) . The base station transmits a contention resolution message to the UE in response to the Msg3 (block 634) . An HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the four-step random access procedure. The following table shows data structure of the RRCResumeRequest1.

Table 8: RRCResumeRequest1

4-step RAP and Msg3 with HARQ-ACK NOT added in “RRCResumeRequest1” :

With reference to FIG. 10, when the UE in an RRC inactive state receives MBMS transmission, the UE triggers a 4-step random access procedure and adds “MBMS-ULFB” as “ResumeCause” into a message Msg3 to perform the 4-step random access procedure. HARQ-ACK for the MBMS transmission is not carried in the message Msg3, represented by the RRCResumeRequest1. An HARQ feedback bit for the MBMS transmission is not included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the four-step random access procedure.

2-step RAP and MsgA with HARQ-ACK added in “RRCResumeRequest1” :

With reference to FIG. 11, when the UE in an RRC inactive state receives MBMS transmission, the UE triggers a 2-step random access procedure and adds “MBMS-ULFB” as “ResumeCause” into a message MsgA to perform the 2-step random access procedure. HARQ-ACK for the MBMS transmission is carried in the message MsgA, represented by a combined request including the RA preamble of the UE and the RRCResumeRequest1.

With reference to FIG. 11, when attempting to transmit an HARQ feedback signal of the MBMS transmission, the UE in the RRC inactive state transmits a combined request MsgA including a random access preamble and the RRCSetupRequest1 to the base station to trigger the RAP (block 741) . The base station receives the combined request MsgA and transmits a combined response as the MsgB including the RAR and the contention resolution message to the UE in response to the Msg A (block 742) . An HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRCSetupRequest1 in the 2-step random access procedure.

2-step RAP and MsgA with HARQ-ACK NOT added in “RRCResumeRequest1” :

With reference to FIG. 11, when the UE in an RRC inactive state receives MBMS transmission, the UE triggers a 2-step random access procedure and adds “MBMS-ULFB” as “ResumeCause” into a message MsgA to perform the 2-step random access procedure. HARQ-ACK for the MBMS transmission is not carried in the message MsgA, represented by a combined request including the RA preamble of the UE and the RRCResumeRequest1. An HARQ feedback bit for the MBMS transmission is not included as the feedback signal of the MBMS transmission in the RRCSetupRequest1 in the 2-step random access procedure.

Feedback resource indication:

An embodiment of feedback resource indication and HARQ information indication is detailed in the following. Either or both of feedback resource indication and HARQ information indication may be include in MBMS configuration indication.

With reference to FIG. 12 and FIG. 13, the base station transmits MBMS transmission in units of MBMS frames, subframe, slots, or sub-slots to a group of UEs, including the UE 10a and UE 10b (block 410) . A UE, such as one of the UE 10a and UE 10b, receives the MBMS transmission from the base station (block 510) .

The base station transmits MBMS configuration indication including feedback resource indication to the UEs, such as the UE 10a and UE10b, to indicate radio resources associated with the feedback channel for MBMS transmission (block 411) . The UEs receives the MBMS configuration indication including the feedback resource indication (block 511) . The MBMS configuration indication including the feedback resource indication may be sent after the RAP is complete. Additionally, the MBMS configuration indication may include HARQ related information indication providing other HARQ related information, such as HARQ process identifier (ID) , redundancy version (RV) , and others.

A UE, such as the UE 10a or UE10b, transmits a feedback signal of the MBMS transmission to the base station through the feedback resources indicated by the indication (block 512) . The BS receives a feedback signal of the MBMS transmission from the UE through the feedback resources indicated by the indication (block 412) .

The BS performs MBMS retransmission in response to the feedback signal (block 413) . The UE receives and decodes MBMS traffic retransmitted by the base station.

MBMS may be realized by MBSFN transmission and SC-PTM transmission. MBMS is a point-to-multipoint interface designed to provide efficient delivery of broadcast and multicast services in 3GPP cellular networks. MBMS delivers multicast services within a single cell using single cell point to multipoint (SC-PTM) transmission, and delivers broadcast services within a group of multiples cells using multimedia broadcast multicast service single frequency network (MBSFN) transmission. SC-PTM uses LTE downlink shared channels and subframe structures for transmission while MBSFN defines new channels and has a subframe structure different than a regular LTE subframe to ensure MBMS transmission over a group of cells.

SC-PTM transmission:

The UE receives and reads a system information block SIB1 to acquire scheduling information of a system information block SIB20, and uses the acquired scheduling information to receives and reads the system information block SIB20. The UE reads the system information block SIB20 to acquire configuration of a single cell multicast control channel (SC-MCCH) . The UE searches type-1A CSS for a DCI identified by a single cell RNTI (SC-RNTI) that schedules the SC-MCCH. The UE reads the SC-MCCH to acquire configuration of a single cell multicast traffic channel (SC-MTCH) , which includes group RNTI (G-RNTI) . The UE searches type-2A CSS for a DCI identified by the G-RNTI that schedules the SC-MTCH (s) . The UE acquires the SC-MTCH (s) carrying SC-PTM service (s) .

When the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication may indicate feedback resources as a resource pool shared by a plurality of UEs. The feedback resource indication indicating the resource pool may be carried in a system information block SIB20, a single cell multicast control channel (SC-MCCH) with single cell RNTI (SC-RNTI) , a multicast traffic channel (MTCH) with group RNTI (G-RNTI) , DCI with SC-RNTI, DCI with G-RNTI, or DCI with C-RNTI. The resource pool may be shared by all UEs associated with the MBMS transmission or a subset of the UEs.

Alternatively, when the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication may indicate feedback resources as a UE-specific resource dedicated to the UE. The feedback resource indication indicating the UE-specific resource may be carried in DCI with C-RNTI. Each UE may use UE-specific resource allocated to the UE for the feedback signal transmission.

The following table shows examples of control signals for carrying the feedback resource indication.

Table 9

MBSFN transmission:

The UE receives and reads a system information block SIB1 to acquire scheduling information of a system information block SIB13, and uses the acquired scheduling information to receives and reads the system information block SIB13. The UE reads the system information block SIB13 to acquire configuration of a multicast control channel (MCCH) . The UE searches type-1A CSS for a DCI identified by a RNTI (RNTI) that schedules the SC-MCCH. The UE reads the MCCH to acquire configuration of a multicast traffic channel (MTCH) , which includes MBMS RNTI (M-RNTI) . The UE searches type-2A CSS for a DCI identified by the M-RNTI that schedules the MTCH (s) . The UE acquires the MTCH (s) carrying MBSFN service (s) .

When the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication may indicate feedback resources as a resource pool shared by a plurality of UEs. The feedback resource indication indicating the resource pool may be carried in a system information block SIB13, a multicast control channel (MCCH) , a medium access control (MAC) control element (CE) with MBMS RNTI (M-RNTI) , downlink control information (DCI) with M-RNTI, or DCI with C-RNTI. The resource pool may be shared by all UEs associated with the MBMS transmission or a subset of the UEs. UEs associated with the MBMS may comprise UEs in a cell or a MBMS area of the MBMS transmission or a group of UEs having subscription to the MBMS transmission.

Alternatively, when the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication may indicate feedback resources as a UE-specific resource dedicated to the UE. The feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI. Each UE may use UE-specific resource allocated to the UE for the feedback signal transmission.

The NW and the UE may use the feedback resources to transmit other HARQ related information, such as HARQ process ID, redundancy version (RV) , and others.

Table 10

FIG. 14 is a block diagram of an example system 700 for wireless communication according to an embodiment of the present disclosure. Embodiments described herein may be implemented into the system using any suitably configured hardware and/or software. FIG. 14 illustrates the system 700 including a radio frequency (RF) circuitry 710, a baseband circuitry 720, a processing unit 730, a memory/storage 740, a display 750, a camera 760, a sensor 770, and an input/output (I/O) interface 780, coupled with each other as illustrated.

The processing unit 730 may include a circuitry, such as, but not limited to, one or more single-core or multi-core processors. The processors may include any combinations of general-purpose processors and dedicated processors, such as graphics processors and application processors. The processors 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 running on the system.

The baseband circuitry 720 may include a circuitry, such as, but not limited to, one or more single-core or multi-core processors. The processors may include a baseband processor. The baseband circuitry may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry. The radio control functions may include, but are not limited to, signal modulation, encoding, decoding, radio frequency shifting, etc. In some embodiments, the baseband circuitry may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry may support communication with 5G NR, LTE, an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN) , a wireless local area network (WLAN) , a wireless personal area network (WPAN) . Embodiments in which the baseband circuitry is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry. In various embodiments, the baseband circuitry 720 may include circuitry to operate with signals that are not strictly considered as being in a baseband frequency. For example, in some embodiments, baseband circuitry may include circuitry to operate with signals having an intermediate frequency, which is between a baseband frequency and a radio frequency.

The RF circuitry 710 may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. In various embodiments, the RF circuitry 710 may include circuitry to operate with signals that are not strictly considered as being in a radio frequency. For example, in some embodiments, RF circuitry may include circuitry to operate with signals having an intermediate frequency, which is between a baseband frequency and a radio frequency.

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

The memory/storage 740 may be used to load and store data and/or instructions, for example, for system. The memory/storage for one embodiment may include any combination of suitable volatile memory, such as dynamic random access memory (DRAM) ) , and/or non-volatile memory, such as flash memory. In various embodiments, the I/O interface 780 may include one or more user interfaces designed to enable user interaction with the system and/or peripheral component interfaces designed to enable peripheral component interaction with the system. User interfaces may include, but are not limited to a physical keyboard or keypad, a touchpad, a speaker, a microphone, etc. 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 supply interface.

In various embodiments, the sensor 770 may include one or more sensing devices to determine environmental conditions and/or location information related to the system. In some embodiments, the sensors may include, but are not limited to, a gyro 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, the baseband circuitry and/or RF circuitry to communicate with components of a positioning network, e.g., a global positioning system (GPS) satellite. In various embodiments, the display 750 may include a display, such as a liquid crystal display and a touch screen display. In various embodiments, the 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, etc. In various embodiments, system may have more or less components, and/or different architectures. Where appropriate, 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.

The embodiment of the present disclosure is a combination of techniques/processes that can be adopted in 3GPP specification to create an end product.

A person having ordinary skill in the art understands that each of the units, algorithm, and steps described and disclosed in the embodiments of the present disclosure are realized using electronic hardware or combinations of software for computers and electronic hardware. Whether the functions run in hardware or software depends on the condition of application and design requirement for a technical plan. A person having ordinary skill in the art can use different ways to realize the function for each specific application while such realizations should not go beyond the scope of the present disclosure. It is understood by a person having ordinary skill in the art that he/she can refer to the working processes of the system, device, and unit in the above-mentioned embodiment since the working processes of the above-mentioned system, device, and unit are basically the same. For easy description and simplicity, these working processes will not be detailed.

It is understood that the disclosed system, device, and method in the embodiments of the present disclosure can be realized with other ways. The above-mentioned embodiments are exemplary only. The division of the units is merely based on logical functions while other divisions exist in realization. It is possible that a plurality of units or components are combined or integrated in another system. It is also possible that some characteristics are omitted or skipped. On the other hand, the displayed or discussed mutual coupling, direct coupling, or communicative coupling operate through some ports, devices, or units whether indirectly or communicatively by ways of electrical, mechanical, or other kinds of forms.

The units as separating components for explanation are or are not physically separated. The units for display are or are not physical units, that is, located in one place or distributed on a plurality of network units. Some or all of the units are used according to the purposes of the embodiments. Moreover, each of the functional units in each of the embodiments can be integrated in one processing unit, physically independent, or integrated in one processing unit with two or more than two units.

If the software function unit is realized and used and sold as a product, it can be stored in a readable storage medium in a computer. Based on this understanding, the technical plan proposed by the present disclosure can be essentially or partially realized as the form of a software product. Or, one part of the technical plan beneficial to the conventional technology can be realized as the form of a software product. The software product in the computer is stored in a storage medium, including a plurality of commands for a computational device (such as a personal computer, a server, or a network device) to run all or some of the steps disclosed by the embodiments of the present disclosure. The storage medium includes a USB disk, a mobile hard disk, a read-only memory (ROM) , a random access memory (RAM) , a floppy disk, or other kinds of media capable of storing program codes.

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

Claims

A method executable in a user equipment (UE) , comprising:

transmitting a request for establishment of a feedback channel for multimedia broadcast multicast services (MBMS) transmission through a random access procedure; and

transmitting a feedback signal of the MBMS transmission through the feedback channel.
The method of claim 1, wherein the feedback channel comprises a new defined uplink channel dedicated to the MBMS transmission, a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) .
The method of claim 1, wherein the UE is in a radio resource control (RRC) idle state before the establishing of the feedback channel, and transits from the RRC idle state to an RRC connected state through the random access procedure.
The method of claim 3, wherein the random access procedure is a four-step random access procedure.
The method of claim 4, wherein the establishment of the feedback channel for the MBMS transmission is included as an establishment cause in an RRC setup request in the four-step random access procedure, wherein the request for establishment of the feedback channel comprises the RRC setup request.
The method of claim 5, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the four-step random access procedure.
The method of claim 3, wherein the random access procedure is a two-step random access procedure.
The method of claim 7, wherein the establishment of the feedback channel for the MBMS transmission is included as an establishment cause in an RRC setup request in the two-step random access procedure, wherein the RRC setup request is combined with a preamble of the UE into a combined request message, and the request for establishment of the feedback channel comprises the combined request message..
The method of claim 8, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the two-step random access procedure.
The method of claim 1, wherein the UE is in an RRC inactive state before the establishment of the feedback channel, and transits from the RRC inactive state to an RRC connected state through the random access procedure.
The method of claim 10, wherein the random access procedure is a four-step random access procedure.
The method of claim 11, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a shorten RRC resume request in the four-step random access procedure, and the request for the establishment of the feedback channel comprises the shorten RRC resume request.
The method of claim 12, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the four-step random access procedure.
The method of claim 11, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a full-length RRC resume request in the four-step random access procedure, and the request for the establishment of the feedback channel comprises the full-length RRC resume request.
The method of claim 14, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the four-step random access procedure.
The method of claim 10, wherein the random access procedure is a two-step random access procedure.
The method of claim 16, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a shorten RRC resume request in the two-step random access procedure, wherein the shorten RRC resume request is combined with a preamble of the UE into a combined request message, and the request for the establishment of the feedback channel comprises the combined request message.
The method of claim 17, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the two-step random access procedure.
The method of claim 16, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a full-length RRC resume request in the two-step random access procedure, wherein the full-length RRC resume request is combined with a preamble of the UE into a combined request message, and the request for the establishment of the feedback channel comprises the combined request message.
The method of claim 19, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the two-step random access procedure.
The method of claim 1, further comprising:

receiving feedback resource indication associated with the feedback channel, which indicates feedback resources allocated for the feedback channel.
The method of claim 21, wherein the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication indicates feedback resources as a resource pool shared by a plurality of UEs.
The method of claim 22, wherein the feedback resource indication indicating the resource pool is carried in a system information block SIB13, a multicast control channel (MCCH) , a medium access control (MAC) control element (CE) with M-RNTI, downlink control information (DCI) with M-RNTI, or DCI with C-RNTI.
The method of claim 21, wherein the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication indicates feedback resources as a UE-specific resource dedicated to the UE.
The method of claim 24, wherein the feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI.
The method of claim 21, wherein the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication indicates feedback resources as a resource pool shared by a plurality of UEs.
The method of claim 26, wherein the feedback resource indication indicating the resource pool is carried in a system information block SIB20, a single cell multicast control channel (SC-MCCH) with single cell RNTI (SC-RNTI) , a multicast traffic channel (MTCH) with group RNTI (G-RNTI) , DCI with SC-RNTI, DCI with G-RNTI, or DCI with C-RNTI.
The method of claim 21, wherein the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication indicates feedback resources as a UE-specific resource dedicated to the UE.
The method of claim 28, wherein the feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI.
The method of claim 21, further comprising:

receiving MBMS configuration indication including at least one of the feedback resource indication and HARQ related information indication, wherein the HARQ related information indication includes at least one of HARQ process identifier (ID) and redundancy version (RV) .
A method executable in a base station, comprising:

receiving a request for establishment of a feedback channel for multimedia broadcast multicast services (MBMS) transmission through a random access procedure; and

receiving a feedback signal of the MBMS transmission through the feedback channel.
The method of claim 31, wherein the feedback channel comprises a new defined uplink channel dedicated to the MBMS transmission, a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) .
The method of claim 31, wherein the random access procedure is associated with an RRC idle state.
The method of claim 33, wherein the random access procedure is a four-step random access procedure.
The method of claim 34, wherein the establishment of the feedback channel for the MBMS transmission is included as an establishment cause in an RRC setup request in the four-step random access procedure, wherein the request for establishment of the feedback channel comprises the RRC setup request.
The method of claim 35, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the four-step random access procedure.
The method of claim 33, wherein the random access procedure is a two-step random access procedure.
The method of claim 37, wherein the establishment of the feedback channel for the MBMS transmission is included as an establishment cause in an RRC setup request in the two-step random access procedure, wherein the RRC setup request is combined with a preamble of the UE into a combined request message, and the request for establishment of the feedback channel comprises the combined request message.
The method of claim 38, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the two-step random access procedure.
The method of claim 31, wherein the random access procedure is associated with an RRC inactive state.
The method of claim 40, wherein the random access procedure is a four-step random access procedure.
The method of claim 41, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a shorten RRC resume request in the four-step random access procedure, and the request for the establishment of the feedback channel comprises the shorten RRC resume request.
The method of claim 42, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the four-step random access procedure.
The method of claim 41, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a full-length RRC resume request in the four-step random access procedure, and the request for the establishment of the feedback channel comprises the full-length RRC resume request.
The method of claim 44, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the four-step random access procedure.
The method of claim 40, wherein the random access procedure is a two-step random access procedure.
The method of claim 46, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a shorten RRC resume request in the two-step random access procedure, wherein the shorten RRC resume request is combined with a preamble of the UE into a combined request message, and the request for the establishment of the feedback channel comprises the combined request message.
The method of claim 47, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the two-step random access procedure.
The method of claim 46, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a full-length RRC resume request in the two-step random access procedure, wherein the full-length RRC resume request is combined with a preamble of the UE into a combined request message, and the request for the establishment of the feedback channel comprises the combined request message.
The method of claim 49, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the two-step random access procedure.
The method of claim 31, further comprising:

transmitting feedback resource indication associated with the feedback channel, which indicates feedback resources allocated for the feedback channel.
The method of claim 51, wherein the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication indicates feedback resources as a resource pool shared by a plurality of UEs.
The method of claim 52, wherein the feedback resource indication indicating the resource pool is carried in a system information block SIB13, a multicast control channel (MCCH) , a medium access control (MAC) control element (CE) with M-RNTI, downlink control information (DCI) with M-RNTI, or DCI with C-RNTI.
The method of claim 51, wherein the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication indicates feedback resources as a UE-specific resource dedicated to the UE.
The method of claim 54, wherein the feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI.
The method of claim 51, wherein the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication indicates feedback resources as a resource pool shared by a plurality of UEs.
The method of claim 56, wherein the feedback resource indication indicating the resource pool is carried in a system information block SIB20, a single cell multicast control channel (SC-MCCH) with single cell RNTI (SC-RNTI) , a multicast traffic channel (MTCH) with group RNTI (G-RNTI) , DCI with SC-RNTI, DCI with G-RNTI, or DCI with C-RNTI.
The method of claim 51, wherein the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication indicates feedback resources as a UE-specific resource dedicated to the UE.
The method of claim 58, wherein the feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI.
The method of claim 51, wherein the processor further executes the step of:

transmitting MBMS configuration indication including at least one of the feedback resource indication and HARQ related information indication, wherein the HARQ related information indication includes at least one of HARQ process identifier (ID) and redundancy version (RV) .
A user equipment comprising:

a transceiver; and

a processor connected with the transceiver and configured to execute the following steps comprising:

transmitting a request for establishment of a feedback channel for multimedia broadcast multicast services (MBMS) transmission through a random access procedure; and

transmitting a feedback signal of the MBMS transmission through the feedback channel.
The user equipment of claim 61, wherein the feedback channel comprises a new defined uplink channel dedicated to the MBMS transmission, a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) .
The user equipment of claim 62, wherein the UE is in a radio resource control (RRC) idle state before the establishing of the feedback channel, and transits from the RRC idle state to an RRC connected state through the random access procedure.
The user equipment of claim 63, wherein the random access procedure is a four-step random access procedure.
The user equipment of claim 64, wherein the establishment of the feedback channel for the MBMS transmission is included as an establishment cause in an RRC setup request in the four-step random access procedure, wherein the request for establishment of the feedback channel comprises the RRC setup request.
The user equipment of claim 65, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the four-step random access procedure.
The user equipment of claim 63, wherein the random access procedure is a two-step random access procedure.
The user equipment of claim 67, wherein the establishment of the feedback channel for the MBMS transmission is included as an establishment cause in an RRC setup request in the two-step random access procedure, wherein the RRC setup request is combined with a preamble of the UE into a combined request message, and the request for establishment of the feedback channel comprises the combined request message..
The user equipment of claim 68, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the two-step random access procedure.
The user equipment of claim 62, wherein the UE is in an RRC inactive state before the establishment of the feedback channel, and transits from the RRC inactive state to an RRC connected state through the random access procedure.
The user equipment of claim 70, wherein the random access procedure is a four-step random access procedure.
The user equipment of claim 71, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a shorten RRC resume request in the four-step random access procedure, and the request for the establishment of the feedback channel comprises the shorten RRC resume request.
The user equipment of claim 72, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the four-step random access procedure.
The user equipment of claim 71, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a full-length RRC resume request in the four-step random access procedure, and the request for the establishment of the feedback channel comprises the full-length RRC resume request.
The user equipment of claim 74, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the four-step random access procedure.
The user equipment of claim 70, wherein the random access procedure is a two-step random access procedure.
The user equipment of claim 76, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a shorten RRC resume request in the two-step random access procedure, wherein the shorten RRC resume request is combined with a preamble of the UE into a combined request message, and the request for the establishment of the feedback channel comprises the combined request message.
The user equipment of claim 77, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the two-step random access procedure.
The user equipment of claim 76, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a full-length RRC resume request in the two-step random access procedure, wherein the full-length RRC resume request is combined with a preamble of the UE into a combined request message, and the request for the establishment of the feedback channel comprises the combined request message.
The user equipment of claim 79, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the two-step random access procedure.
The user equipment of claim 61, wherein the processor further executes the step of:

receiving feedback resource indication associated with the feedback channel, which indicates feedback resources allocated for the feedback channel.
The user equipment of claim 81, wherein the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication indicates feedback resources as a resource pool shared by a plurality of UEs.
The user equipment of claim 82, wherein the feedback resource indication indicating the resource pool is carried in a system information block SIB13, a multicast control channel (MCCH) , a medium access control (MAC) control element (CE) with M-RNTI, downlink control information (DCI) with M-RNTI, or DCI with C-RNTI.
The user equipment of claim 81, wherein the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication indicates feedback resources as a UE-specific resource dedicated to the UE.
The user equipment of claim 84, wherein the feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI.
The user equipment of claim 81, wherein the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication indicates feedback resources as a resource pool shared by a plurality of UEs.
The user equipment of claim 86, wherein the feedback resource indication indicating the resource pool is carried in a system information block SIB20, a single cell multicast control channel (SC-MCCH) with single cell RNTI (SC-RNTI) , a multicast traffic channel (MTCH) with group RNTI (G-RNTI) , DCI with SC-RNTI, DCI with G-RNTI, or DCI with C-RNTI.
The user equipment of claim 81, wherein the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication indicates feedback resources as a UE-specific resource dedicated to the UE.
The user equipment of claim 88, wherein the feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI.
The user equipment of claim 81, wherein the processor further executes the step of:

receiving MBMS configuration indication including at least one of the feedback resource indication and HARQ related information indication, wherein the HARQ related information indication includes at least one of HARQ process identifier (ID) and redundancy version (RV) .
A base station, comprising:

receiving a request for establishment of a feedback channel for multimedia broadcast multicast services (MBMS) transmission through a random access procedure; and

receiving a feedback signal of the MBMS transmission through the feedback channel.
The base station of claim 91, wherein the feedback channel comprises a new defined uplink channel dedicated to the MBMS transmission, a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) .
The base station of claim 91, wherein the random access procedure is associated with an RRC idle state.
The base station of claim 93 , wherein the random access procedure is a four-step random access procedure.
The base station of claim 94, wherein the establishment of the feedback channel for the MBMS transmission is included as an establishment cause in an RRC setup request in the four-step random access procedure, wherein the request for establishment of the feedback channel comprises the RRC setup request.
The base station of claim 95, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the four-step random access procedure.
The base station of claim 93, wherein the random access procedure is a two-step random access procedure.
The base station of claim 97, wherein the establishment of the feedback channel for the MBMS transmission is included as an establishment cause in an RRC setup request in the two-step random access procedure, wherein the RRC setup request is combined with a preamble of the UE into a combined request message, and the request for establishment of the feedback channel comprises the combined request message.
The base station of claim 98, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the RRC setup request in the two-step random access procedure.
The base station of claim 91, wherein the random access procedure is associated with an RRC inactive state.
The base station of claim 100, wherein the random access procedure is a four-step random access procedure.
The base station of claim 101, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a shorten RRC resume request in the four-step random access procedure, and the request for the establishment of the feedback channel comprises the shorten RRC resume request.
The base station of claim 102, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the four-step random access procedure.
The base station of claim 101, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a full-length RRC resume request in the four-step random access procedure, and the request for the establishment of the feedback channel comprises the full-length RRC resume request.
The base station of claim 104, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the four-step random access procedure.
The base station of claim 100, wherein the random access procedure is a two-step random access procedure.
The base station of claim 106, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a shorten RRC resume request in the two-step random access procedure, wherein the shorten RRC resume request is combined with a preamble of the UE into a combined request message, and the request for the establishment of the feedback channel comprises the combined request message.
The base station of claim 107, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the shorten RRC resume request in the two-step random access procedure.
The base station of claim 106, wherein the establishment of the feedback channel for the MBMS transmission is included as a resume cause in a full-length RRC resume request in the two-step random access procedure, wherein the full-length RRC resume request is combined with a preamble of the UE into a combined request message, and the request for the establishment of the feedback channel comprises the combined request message.
The base station of claim 109, wherein an HARQ feedback bit for the MBMS transmission is included as the feedback signal of the MBMS transmission in the full-length RRC resume request in the two-step random access procedure.
The base station of claim 91, wherein the processor further executes the step of:

transmitting feedback resource indication associated with the feedback channel, which indicates feedback resources allocated for the feedback channel.
The base station of claim 111, wherein the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication indicates feedback resources as a resource pool shared by a plurality of UEs.
The base station of claim 112, wherein the feedback resource indication indicating the resource pool is carried in a system information block SIB13, a multicast control channel (MCCH) , a medium access control (MAC) control element (CE) with M-RNTI, downlink control information (DCI) with M-RNTI, or DCI with C-RNTI.
The base station of claim 111 wherein the MBMS transmission is performed via multicast broadcast single frequency network (MBSFN) , the feedback resource indication indicates feedback resources as a UE-specific resource dedicated to the UE.
The base station of claim 114, wherein the feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI.
The base station of claim 111, wherein the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication indicates feedback resources as a resource pool shared by a plurality of UEs.
The base station of claim 116, wherein the feedback resource indication indicating the resource pool is carried in a system information block SIB20, a single cell multicast control channel (SC-MCCH) with single cell RNTI (SC-RNTI) , a multicast traffic channel (MTCH) with group RNTI (G-RNTI) , DCI with SC-RNTI, DCI with G-RNTI, or DCI with C-RNTI.
The base station of claim 111, wherein the MBMS transmission is performed via single-cell point-to-multipoint (SC-PTM) , the feedback resource indication indicates feedback resources as a UE-specific resource dedicated to the UE.
The base station of claim 118, wherein the feedback resource indication indicating the UE-specific resource is carried in DCI with C-RNTI.
The base station of claim 111, wherein the processor further executes the step of:

transmitting MBMS configuration indication including at least one of the feedback resource indication and HARQ related information indication, wherein the HARQ related information indication includes at least one of HARQ process identifier (ID) and redundancy version (RV) .
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 execute any of the methods of claims 1 to 30.
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 execute any of the methods of claims 31 to 60.
A computer readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute any of the methods of claims 1 to 30.
A computer readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute any of the methods of claims 31 to 60.
A computer program product, comprising a computer program, wherein the computer program causes a computer to execute any of the methods of claims 1 to 30.
A computer program product, comprising a computer program, wherein the computer program causes a computer to execute any of the methods of claims 31 to 60.
A computer program, wherein the computer program causes a computer to execute any of the methods of claims 1 to 30.
A computer program, wherein the computer program causes a computer to execute any of the methods of claims 31 to 60.