WO2021072739A1

WO2021072739A1 - Information sending method and apparatus, terminal, access network device and system

Info

Publication number: WO2021072739A1
Application number: PCT/CN2019/111936
Authority: WO
Inventors: Cong SHI; Zhe FU
Original assignee: Guangdong Oppo Mobile Telecommunications Corp., Ltd.
Priority date: 2019-10-18
Filing date: 2019-10-18
Publication date: 2021-04-22
Also published as: CN114503476A; CN114503476B

Abstract

Provided are a method and user equipment (UE) for retransmission. In the method, a UE receives an uplink grant (UL) for retransmission from a gNodeB (gNB), and the UE determines whether to ignore the UL grant.

Description

INFORMATION SENDING METHOD AND APPARATUS, TERMINAL, ACCESS NETWORK DEVICE AND SYSTEM

TECHNICAL FIELD

The disclosure relates to a field of communications, and particularly to, a method and user equipment (UE) for retransmission.

BACKGROUND

In RAN2#107bis Chongqing Meeting, it has agreed:

Chair summary:

-Everyone think that gNB scheduled retransmission of a deprioritized transmission shall be supported (acc to earlier agreement) .

-There is significant support to allow “UE autonomous retransmission in a CG resource” . For this case MAC will not re-generate a PDU, but it is open whether the transmission would be considered a HARQ new transmission or a HARQ retransmission.

-There is no consensus to make additional effort if needed to speed up a retransmission by using another HARQ process.

-It seems not clear if the NR-U solution could be reused.

SUMMARY

In a first aspect, there is provided a method for retransmission, including: receiving, by a user equipment (UE) , an uplink grant (UL) for retransmission from a gNodeB (gNB) ; and determining, by the UE, whether to ignore the UL grant.

In an embodiment, the determining, by the UE, whether to ignore the UL grant includes: if the UL grant received on Physical Downlink Control Channel (PDCCH) is addressed to Configured Scheduling Radio Network Tempory Identity (CS-RNTI) and if a Hybrid Auto Retransfer Request (HARQ) buffer of an identified process is empty due to a collision between UL transmission of CG resources and other UL transmissions, determining, by the UE, deprioritizing of the transmission of the CG resources.

In an embodiment, the determining, by the UE, whether to ignore the UL grant includes: if the UL grant received on Physical Downlink Control Channel (PDCCH) is addressed to Configured Scheduling Radio Network Tempory Identity (CS-RNTI) and if a Hybrid Auto Retransfer Request (HARQ) buffer of an identified process is empty due to no data available for CG resources which collides with other UL transmission, not ignoring, by the UE, the UL grant.

In a second aspect, there is provided a user equipment (UE) for retransmission, including: a transceiver, configured to receive an uplink grant (UL) for retransmission from a gNodeB (gNB) ; and at least one processor, configured to determine whether to ignore the UL grant.

In an embodiment, the processor is configured to: if the UL grant received on Physical Downlink Control Channel (PDCCH) is addressed to Configured Scheduling Radio Network Tempory Identity (CS-RNTI) and if a Hybrid Auto Retransfer Request (HARQ) buffer of an identified process is empty due to a collision between UL transmission of CG resources and other UL transmissions, determine deprioritizing of the transmission of the CG resources.

In an embodiment, the processor is configured to: if the UL grant received on Physical Downlink Control Channel (PDCCH) is addressed to Configured Scheduling Radio Network Tempory Identity (CS-RNTI) and if a Hybrid Auto Retransfer Request (HARQ) buffer of an identified process is empty due to no data available for CG resources which collides with other UL transmission, not ignore the UL grant.

BRIEF DESCRIPTION OF DRAWINGS

In order to describe the technical solutions in the embodiments of the present disclosure more clearly, the drawings required to be used in descriptions about the embodiments will be simply introduced below. Obviously, the drawings in the following descriptions are only some embodiments of the present disclosure. Those of ordinary skill in the art may further obtain other drawings according to these drawings without creative work.

FIG. 1 is a schematic structure diagram of a mobile communication system according to an exemplary embodiment of the present disclosure.

FIG. 2 is a flow chart showing a method for retransmission according to an embodiment of the disclosure.

FIG. 3 is a schematic structure diagram of a UE according to an embodiment of the present disclosure.

FIG. 4 is a schematic structure diagram of a network device according to an embodiment of the present disclosure.

FIG. 5 is a schematic structure diagram of a UE according to an exemplary embodiment of the present disclosure.

FIG. 6 is a schematic structure diagram of a network device according to an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION

In order to make the objectives, technical solutions and advantages of the present disclosure clearer, the implementation manners of the present disclosure will be further described in detail in conjunction with the accompanying drawings.

"Module" as referred to herein generally refers to a program or instruction stored in a memory that is capable of performing certain functions. "Unit" as referred to herein generally refers to a functional structure that is logically divided. The "unit" may be implemented by pure hardware or a combination of hardware and software.

"Multiple" as referred to herein means two or more. The term "and/or" is an association describing associated objects, indicating that there may be three relationships. For example, A and/or B may indicate that A exists separately, both A and B exist simultaneously, and B exists separately. The character "/" generally indicates that the contextual object is an "or" relationship. The words "first" , "second" and similar terms used in the specification and claims of the present disclosure do not denote any order, quantity, or importance, but are merely used to distinguish different components.

Referring to FIG. 1, it shows a schematic structure diagram of a mobile communication system according to an embodiment of the present disclosure. The mobile communication system may be a 5G system, also known as an NR system. The mobile communication system includes an access network device 120 and a terminal 140.

The access network device 120 may be a base station. For example, the base station may be a base station (gNB) employing a central distributed architecture in the 5G system. When the access network device 120 employs the central distributed architecture, it generally includes a Central Unit (CU) and at least two Distributed Units (DUs) . The CU is provided with protocol stacks of a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, and a Media Access Control (MAC) layer. The DU is provided with a physical (PHY) layer protocol stack. The specific implementation manner of the access network device 120 in the embodiment of the present disclosure is not limited. Optionally, the access network device may further include a Home eNB (HeNB) , a relay, a pico, and the like.

The access network device 120 and the terminal 140 establish a wireless connection through a wireless radio. Optionally, the wireless radio is a wireless radio based on a fifth generation mobile communication network technology (5G) standard. For example, the wireless NR is an NR; or the wireless radio may also be a wireless radio based on the next generation mobile communication network technology standard of 5G.

The terminal 140 may be a device that provides voice and/or data connectivity to a user. The terminal may communicate with one or more core networks through a Radio Access Network (RAN) . For example, the terminal 140 may be a mobile terminal such as a mobile phone (or a "cellular" phone) and a computer with a mobile terminal. For example, the terminal may also be a portable, pocket-sized, hand-held, computer-integrated or in-vehicle mobile device. For example, it is a subscriber unit, a subscriber station, a mobile station, a mobile, a remote station, an access point, a remote terminal, an access terminal, a user terminal, a user agent, a user device, or a user equipment.

It should be noted that, in the mobile communication system shown in FIG. 1, multiple access network devices 120 and/or multiple terminals 140 may be included. One access network device 120 and one terminal 140 shown in FIG. 1 are taken as an example, but the present embodiment does not limit this.

In RAN2#107bis Chongqing Meeting, it has agreed:

Chair summary:

- Everyone think that gNB scheduled retransmission of a deprioritized transmission shall be supported (acc to earlier agreement) .

- There is significant support to allow “UE autonomous retransmission in a CG resource” . For this case MAC will not re-generate a PDU, but it is open whether the transmission would be considered a HARQ new transmission or a HARQ retransmission.

- There is no consensus to make additional effort if needed to speed up a retransmission by using another HARQ process.

- It seems not clear if the NR-U solution could be reused.

There is support to have “UE autonomous retransmission in a CG resource” . Allow checking of complexity to next meeting.

Regarding the first bullet of chairman summary, gNB scheduled retransmission of a deprioritized transmission shall be supported, which means when a UE determines to deprioritize a transmission due to this transmission collides with another UL transmission, the UE can rely on the retransmission scheduling from gNB for the deprioritized UL transmission. There maybe a corresponding MAC PDU stored in a HARQ buffer if the UE has generated the MAC PDU for the deprioritized UL transmission.

Regarding the second bullet of chairman summary, it seems majority views are that the UE will perform autonomous retransmission in a CG resource if the MAC PDU is deprioritized when the CG collides with another UL transmission which has higher priority. The autonomous retransmission, in our understanding, means that if there is a generated deprioritized MAC PDU which is stored in a HARQ buffer with HARQ process ID#n, UE can use the next CG resources with the same HARQ process ID #n to transmit this stored deprioritzed MAC PDU.

Issue:

gNB is not aware of whether the deprioritize MAC PDU is generated or not, because it’s done in the UE side. Then, it could be possible the HARQ buffer is empty when UE receives the retransmission grant (according to bullet#1) from the gNB. In this case, according to the legacy behavior in current MAC specification (5.4.2.1 HARQ Entity) , UE just ignores the UL grant for retransmission, as shown in the following:

2> else (i.e. retransmission) :

3> if the uplink grant received on PDCCH was addressed to CS-RNTI and if the HARQ buffer of the identified process is empty; or

3> if the uplink grant is part of a bundle and if no MAC PDU has been obtained for this bundle; or

3> if the uplink grant is part of a bundle of the configured uplink grant, and the PUSCH of the uplink grant overlaps with a PUSCH of another uplink grant received on the PDCCH or in a Random Access Response for this Serving Cell:

4> ignore the uplink grant.

The issue is that, if the UE always ignores the retransmission grant when the HARQ buffer is empty due to the UE does not generate the deprioritized the MAC PDU or no available data for CG, there could be extra delay/resource wastage when there is new data available in the LCH which should be transmitted as soon as possible, and the available data can be allowed to be transmitted in the received UL grant for retransmission.

Solution:

The solution is that:

1. When the UE receives a UL grant for retransmission, which means the NDI is not toggled and the RVI is set to a specific value by gNB;

2. If the UL grant received on PDCCH was addressed to CS-RNTI and if the HARQ buffer of the identified process is empty due to the collision between UL transmission of the CG resources and other UL transmissions, and the UE determined to deprioritize the CG transmission; or,

3. If the UL grant received on PDCCH was addressed to CS-RNTI and if the HARQ buffer of the identified process is empty due to no data available for the CG resources which collides with other UL transmission:

UE does not ignore the UL grant;

4. If the UL grant is not ignored by the UE due to above condtions are met, and the UE does not generate the deprioritized MAC PDU for the CG resources:

a. obtain a MAC PDU to transmit from the Multiplexing and assembly entity, if any;

5. If the UL grant is not ignored by the UE due to above condtions are met, and the UE has generated the deprioritized MAC PDU for the CG resources:

a. obtain the deprioritized MAC PDU from the corresponding HARQ process;

6. if a MAC PDU to transmit has been obtained according to 4 or 5:

a. deliver the MAC PDU and the retransmission uplink grant and the HARQ information of the TB to the identified HARQ process;

b. instruct the identified HARQ process to trigger a transmission;

c. if the uplink grant is addressed to CS-RNTI; or

d. if the uplink grant is a configured uplink grant; or

e. if the uplink grant is addressed to C-RNTI, and the identified HARQ process is configured for a configured uplink grant:

i. start or restart the configuredGrantTimer, if configured, for the corresponding HARQ process when the transmission is performed.

7. Else (meaning there are no available data to be transmistted) :

a. UE ignores the UL grant;

8. Regarding “instruct the identified HARQ process to trigger a transmission; ” , it could be :

a. New transmission, or

b. Retransmission;

FIG. 2 is a flow chart showing a method for retransmission according to an embodiment of the present disclosure.

In S202, a UE receives an uplink grant (UL) for retransmission from a gNodeB (gNB) .

In S204, the UE determines whether to ignore the UL grant.

The following is a device embodiment of an embodiment of the present disclosure. For the parts that are not elaborated in the device embodiment, reference may be made to the technical details disclosed in the foregoing method embodiments.

Referring to Fig. 3, it shows a schematic structure diagram of a UE according to an embodiment of the present disclosure. The UE may include a processing unit 301, a receiving unit 302 and a sending unit 303.

The determining unit 301 is configured to perform the above steps 301 and other functions of at least one determining step or calculating step explicit or implicit.

The receiving unit 302 is configured to perform the function of at least one receiving step explicit or implicit in the foregoing method embodiment.

The sending unit 303 is configured to perform the functions of steps relating to sending in the above embodiments.

Referring to Fig. 4, it shows a schematic structure diagram of a network device according to an embodiment of the present disclosure. The network device may include a processing unit 401, a sending unit 402 and a receiving unit 403.

The processing unit 401 is configured to perform the functions of determining or calculating steps explicit or implicit.

The sending unit 402 is configured to perform the function of at least one sending step explicit or implicit in the foregoing method embodiment.

The receiving unit 403 is configured to perform the functions of receiving steps explicit or implicit.

Referring to FIG. 5, it shows a schematic structure diagram of a UE according to an exemplary embodiment of the present disclosure. The UE may include a processor 11, a receiver 12, a transmitter 13, a memory 14 and a bus 15.

The processor 11 includes one or more than one processing core, and the processor 11 runs software programs and modules, thereby executing various function applications and information processing.

The receiver 12 and the transmitter 13 may be implemented into a communication component. The communication component may be a communication chip. The communication chip may include a receiving module, a transmission module, a modem module and the like, and is configured to modulate and/or demodulate information and receive or send the information through a wireless signal.

The memory 14 is connected with the processor 11 through the bus 15.

The memory 14 may be configured to store the software programs and the modules.

The memory 14 may store an application program module 16 for at least one function. The application program module 16 may include a processing module 161, a receiving module 162 and a sending module 163.

The processor 11 is configured to execute the processing module 161 to realize a function of a related determining or calculating step in each method embodiment. The processor 11 is configured to execute the sending module 162 to realize a function of a related sending step in each method embodiment. The processor 11 is configured to execute the receiving module 163 to realize a function of a related receiving step in each method embodiment.

In addition, the memory 14 may be implemented by a volatile or nonvolatile storage device of any type or a combination thereof, for example, a Static Random Access Memory (SRAM) , an Electrically Erasable Programmable Read-Only Memory (EEPROM) , an Erasable Programmable Read-Only Memory (EPROM) , a Programmable Read-Only Memory (PROM) , a Read-Only Memory (ROM) , a magnetic memory, a flash memory, a magnetic disk or an optical disk.

Referring to FIG. 6, it shows a schematic structure diagram of a network device according to an exemplary embodiment of the present disclosure. The network device includes: a processor 21, a receiver 22, a transmitter 23, a memory 24 and a bus 25.

The processor 21 includes one or more than one processing core, and the processor 21 runs software programs and modules, thereby executing various function applications and information processing.

The receiver 22 and the transmitter 23 may be implemented into a communication component. The communication component may be a communication chip. The communication chip may include a receiving module, a transmission module, a modem module and the like, and is configured to modulate and demodulate information and receive or send the information through a wireless signal.

The memory 24 is connected with the processor 21 through the bus 25.

The memory 24 may be configured to store the software programs and the modules.

The memory 24 may store an application program module 26 for at least one function. The application program module 26 may include a generation module 261, a sending module 262 and a receiving module 263.

The processor 21 is configured to execute the receiving module 263 to realize a function of a related receiving step in each method embodiment. The processor 21 is configured to execute the processing module 261 to realize a function of a related determining or calculating step in each method embodiment. The processor 21 is configured to execute the sending module 262 to realize a function of a related sending step in each method embodiment.

In addition, the memory 24 may be implemented by a volatile or nonvolatile storage device of any type or a combination thereof, for example, an SRAM, an EEPROM, an EPROM, a PROM, a ROM, a magnetic memory, a flash memory, a magnetic disk or an optical disk.

The embodiment of the present disclosure further provides a system, which may include a UE and a network device.

The UE may include the information receiving device provided in FIG. 4, and the network device may be the network device provided in FIG. 3.

Alternatively, the UE may be the terminal provided in FIG. 5, and the network device may be the access network device provided in FIG. 6.

Those skilled in the art may realize that, in one or more above-mentioned examples, the functions described in the embodiments of the present disclosure may be realized through hardware, software, firmware or any combination thereof. When being realized through the software, these functions may be stored in a computer-readable medium or transmitted as one or more instructions or codes in the computer-readable medium. The computer-readable medium includes a computer storage medium and a communication medium, and the communication medium includes any medium for transmitting a computer program from one place to another place. The storage medium may be any available medium accessible for a universal or dedicated computer.

The above is only the preferred embodiment of the present disclosure and not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements and the like made within the spirit and principle of the present disclosure shall fall within the scope of protection of the present disclosure.

Claims

A method for retransmission, comprising:

receiving, by a user equipment (UE) , an uplink grant (UL) for retransmission from a gNodeB (gNB) ;

determining, by the UE, whether to ignore the UL grant.
The method of claim 1, wherein the determining, by the UE, whether to ignore the UL grant comprises:

if the UL grant received on Physical Downlink Control Channel (PDCCH) is addressed to Configured Scheduling Radio Network Tempory Identity (CS-RNTI) and if a Hybrid Auto Retransfer Request (HARQ) buffer of an identified process is empty due to a collision between UL transmission of CG resources and other UL transmissions, determining, by the UE, deprioritizing of the transmission of the CG resources.
The method of claim 1, wherein the determining, by the UE, whether to ignore the UL grant comprises:

if the UL grant received on Physical Downlink Control Channel (PDCCH) is addressed to Configured Scheduling Radio Network Tempory Identity (CS-RNTI) and if a Hybrid Auto Retransfer Request (HARQ) buffer of an identified process is empty due to no data available for CG resources which collides with other UL transmission, not ignoring, by the UE, the UL grant.
A user equipment (UE) for retransmission, comprising:

a transceiver, configured to receive an uplink grant (UL) for retransmission from a gNodeB (gNB) ;

at least one processor, configured to determine whether to ignore the UL grant.
The UE of claim 4, wherein the processor is configured to:

if the UL grant received on Physical Downlink Control Channel (PDCCH) is addressed to Configured Scheduling Radio Network Tempory Identity (CS-RNTI) and if a Hybrid Auto Retransfer Request (HARQ) buffer of an identified process is empty due to a collision between UL transmission of CG resources and other UL transmissions, determine deprioritizing of the transmission of the CG resources.
The UE of claim 4, wherein the processor is configured to:

if the UL grant received on Physical Downlink Control Channel (PDCCH) is addressed to Configured Scheduling Radio Network Tempory Identity (CS-RNTI) and if a Hybrid Auto Retransfer Request (HARQ) buffer of an identified process is empty due to no data available for CG resources which collides with other UL transmission, not ignore the UL grant.