WO2019184867A1

WO2019184867A1 - Air interface link congestion feedback method, apparatus and device, and storage medium

Info

Publication number: WO2019184867A1
Application number: PCT/CN2019/079506
Authority: WO
Inventors: 王丽萍; 谢峰; 王明月; 戚涛; 何哲
Original assignee: 中兴通讯股份有限公司
Priority date: 2018-03-26
Filing date: 2019-03-25
Publication date: 2019-10-03
Also published as: CN110366202A; CN110366202B

Abstract

Provided are an air interface link congestion feedback method, apparatus and device, and a computer-readable storage medium. The air interface link congestion feedback method comprises the following steps: a DU performing congestion detection on a downlink; upon detection of downlink congestion, generating congestion indication information; and reporting the congestion indication information to a CU, so that the CU performs link adjustment according to the congestion indication information.

Description

Air interface link congestion feedback method, device and device, and storage medium

Technical field

The present disclosure relates to the field of communication technology.

Background technique

In the new air interface technology in the new radio (New Radio, also known as 5G NR), the base station on the radio access network side of the 5G network introduces a centralized unit-distributed unit (CU-DU). Architecture, a base station contains a CU, at least one DU. In the dual-connection architecture, after the data reaches the CU side from the core network, the F1 interface can be used to split the traffic between the two DUs. The CU reports the DDDS (Down-Link Data Delivery) through the DU-side periodic feedback or on-demand feedback flow control status. Status, DL data transfer status) to implement flow control processing of the link. The DDDS mainly includes the data amount that the current data radio bearer (DRB) of the DU and the user equipment/user (UE) need to apply to the CU side, and the packet information of the F1 link that is detected by the DU side, The packet information of the continuous transmission of the DU side air interface. The CU side can learn the data demand on the DU side through DDDS and perform corresponding data flow allocation. It can also learn the data transmission status of the F1 link and perform corresponding F1 data link switching or forwarding.

In some cases, the scheme for performing congestion judgment to adjust the offload or link transition has a large delay, and it is difficult to meet the technical requirements of high-speed transmission and fast handover of 5G. Therefore, there is a need for a method for enabling a CU to quickly determine whether a DU is congested in a case where the CU is separated from the DU, thereby adjusting the link processing policy in time.

Summary of the invention

According to an aspect of an embodiment of the present disclosure, a method for air interface link congestion feedback is provided, the method comprising: a distribution unit DU performing congestion detection on a downlink; and detecting downlink congestion, generating congestion indication information And reporting the congestion indication information to the central unit CU, so that the CU performs link adjustment according to the congestion indication information.

According to another aspect of the embodiments of the present disclosure, there is provided an air interface link congestion feedback apparatus, the apparatus comprising: a distribution unit DU configured to perform congestion detection on a downlink; and if downlink congestion is detected, Generating the congestion indication information; reporting the congestion indication information to the CU; and the central unit CU, configured to acquire the congestion indication information reported by the DU; and perform link adjustment according to the congestion indication information.

According to another aspect of an embodiment of the present disclosure, there is provided an air interface link congestion feedback device, the device comprising: a memory, a processor, and an air interface link stored on the memory and operable on the processor a congestion feedback procedure, the step of implementing the air interface link congestion feedback method described above when the air interface link congestion feedback procedure is executed by the processor.

According to another aspect of the embodiments of the present disclosure, a computer readable storage medium is provided, the air interface link congestion feedback program is stored on the computer readable storage medium, and the air interface link congestion feedback program is executed by a processor The steps of the air interface link congestion feedback method described above are implemented.

DRAWINGS

FIG. 1 is a schematic structural diagram of an internal user plane protocol stack of an NR base station (eg, gNB).

Figure 2 is a schematic diagram of data splitting between two DUs of the same CU.

3 is a schematic diagram of duplication transmission of data between two DUs of the same CU;

Figure 4 is a schematic diagram of NR-NR dual connections between different CUs.

FIG. 5 is a schematic diagram of Long Term Evolution NR (LTE-NR) dual connectivity between different CUs.

FIG. 6 is a schematic flow chart of a method for air interface link congestion feedback according to an embodiment of the present disclosure.

FIG. 7 is a schematic structural diagram of an air interface link congestion feedback apparatus according to an embodiment of the present disclosure.

FIG. 8 is a timing diagram of congestion processing in the case where data is split between two DUs under the same CU according to an embodiment of the present disclosure.

9 is a timing diagram of congestion processing for data transmission between two DUs under the same CU according to an embodiment of the present disclosure.

FIG. 10 is a timing diagram of congestion processing in the case of NR-NR dual connectivity between different CUs according to an embodiment of the present disclosure.

11 is a timing diagram of congestion processing in the case of LTE-NR dual connectivity between different CUs according to an embodiment of the present disclosure.

FIG. 12 is a schematic structural diagram of an air interface link congestion feedback apparatus according to an embodiment of the present disclosure.

The implementation, functional features and advantages of the present disclosure will be further described with reference to the accompanying drawings.

detailed description

The present disclosure will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the disclosure and are not intended to limit the disclosure.

For example, as shown in FIG. 1 , from the perspective of a protocol stack, the CU side includes a Service Data Adaptation Protocol (SDAP) layer and a Packet Data Convergence Protocol (PDCP) layer, and a DU. The side includes a Radio Link Control (RLC) layer and a Medium Access Control (MAC) layer and a Physical Layer (PHY). The interface between the CU and the DU is the F1 interface. In FIG. 1, Ng-U is an interface for providing User Plane Protocol Data Unit (PDU) transmission, Uu is an interface, and GTP-U refers to a general packet radio service of the user plane (General Packet) Radio Service, GPRS) tunneling protocol, UDP refers to the user datagram protocol, IP refers to the Internet interconnection protocol, DLL refers to the data link layer, and the "-U" suffix can refer to the user. surface.

Figure 2 shows a scenario where data is split between two DUs of the same CU. After the data arrives at the CU side, the CU decides through the flow control algorithm and divides the data between the two DUs in a certain proportion. The UE receives the downlink data of the two DUs and summarizes them.

Figure 3 shows a scenario where data is duplicated between two DUs of the same CU. After the data arrives at the CU side, duplication transmission is performed at the PDCP layer of the CU, that is, the same data is copied and simultaneously transmitted to two DUs, and the UE simultaneously receives the same data from the two DUs and performs repeated packet reception processing.

Figure 4 shows an NR-NR dual connectivity scenario between CUs. After the data arrives at the primary base station, the CU side of the primary base station decides through the flow control algorithm and divides the data between the two base stations through the Xn interface in a certain proportion. The UE receives the downlink data of the two base stations and summarizes them.

Figure 5 shows an inter-CU LTE-NR (4G and 5G) dual connectivity scenario. After the data arrives at the primary base station, the CU side of the primary base station decides through the flow control algorithm and divides the data between the two base stations through the Xn interface in a certain proportion. The UE receives the downlink data of the two base stations and summarizes them.

In the application scenario listed above, the CU side can understand the transmission status of the DU air interface to a certain extent through the DDDS, and then use the flow control algorithm to determine whether the DU is congested, so as to determine whether to change the corresponding offload policy or perform link conversion. However, in the case of using such a mechanism to perform congestion judgment to adjust the offload or link conversion, the delay is large, and it is difficult to meet the technical requirements of high-speed transmission and fast handover of 5G.

In this regard, as shown in FIG. 6 , an embodiment of the present disclosure provides a method for air interface link congestion feedback, where the method includes steps S11 to S13 .

At step S11, the DU performs congestion detection on the downlink.

In the embodiment of the present disclosure, the DU performs congestion detection on the downlink based on at least one of the following information: a CQI (Channel Quality Indicator) measurement report reported by the terminal, and a SRS (Sounding Reference Signal) Reference signal) measurement, downlink buffer data transmission delay, RLC retransmission times, HARQ (Hybrid Automatic Repeat reQuest) retransmission times.

At step S12, in the case where downlink congestion is detected, congestion indication information is generated.

In the embodiment of the present disclosure, if the downlink congestion is detected, generating the congestion indication information includes the following steps: if downlink congestion is detected, calculating a congestion SN (Sequence Number) and the congestion SN As the congestion indication information, the bearer level data request amount is set to zero and the bearer level data request amount set to zero is used as the congestion indication information. It should be noted that, in order for the CU to obtain the reported congestion indication information and perform link adjustment according to the congestion indication information, the bearer level data application quantity may be set to zero multiple times, and the bearer level data application quantity is set to zero times. There are no restrictions here.

In an embodiment of the present disclosure, the congestion SN may be calculated based on at least one of the following: a data buffer condition of the DU, status report information fed back by the user terminal, an air interface link condition, HARQ information of the MAC, and ARQ of the RLC ( Automatic Repeat reQuest, automatic retransmission request) information.

In the embodiment of the present disclosure, the calculating the congestion sequence number may include the following steps: calculating a sequence number of the largest data packet that the DU can currently process, and using the sequence number of the data packet as a congestion sequence number.

At step S13, the congestion indication information is reported to the CU, so that the CU performs link adjustment according to the congestion indication information.

In the embodiment of the present disclosure, the DU reports the congestion indication information to the CU through the DDDS, and after the CU obtains the congestion indication information reported by the DU, the CU performs link adjustment according to the congestion indication information.

In order to better illustrate the embodiments of the present disclosure, the following description of the air interface link congestion feedback is illustrated in the application scenarios of FIG. 2 to FIG.

As shown in Figure 2, data is split between two DUs in the same CU. The data is split between the two stations in the CU through two F1 interfaces. The terminal receives the downlink data and performs reordering processing on the two DUs. .

When detecting the congestion of the DU1 downlink through the link detection, the DU1 calculates the information of the largest data packet that the current DU1 can process, and uses the SN of the data packet as the congestion SN. The DDDS carries the congestion SN and goes to the CU through the F1 interface. Reported that DU1 is congested. Alternatively, the DU1 sets the bearer-level data request quantity to zero in the DDDS, and carries the information that the bearer-level data request quantity is set to zero in the DDDS, and reports the DU1 congestion to the CU through the F1 interface.

The CU side knows that the DU1 is congested, and the suspension continues to send downlink data to the DU1; meanwhile, the subsequent data packet is sent through the other side DU2. The UE receives data through DU2.

As shown in Figure 3, data is duplicated between two DUs of the same CU. The data is duplicated between the two stations in the CU through two F1 interfaces. The terminal receives the same downlink data through two DUs and repeats the packet. deal with.

The CU side knows that the DU1 is congested, closes the duplication function on the DU1 side, and suspends the transmission of the downlink duplication data to the DU1; the CU side continues to transmit the downlink data through the DU2. The UE receives data through DU2.

As shown in FIG. 4, the NR-NR is dual-connected between different CUs, and the data is shunted between the two NR base station stations through the Xn interface in the primary CU1, and the terminal receives the downlink data of the offload from the two NR base stations through the dual connection and performs reordering. deal with.

When the secondary DU2 detects the congestion of the DU2 downlink through the link detection, it calculates the information of the largest data packet that can be processed by the current DU2, and uses the SN of the data packet as the congestion SN; carries the congestion SN in the DDDS, and sends the congestion SN through the Xn interface. The main CU1 reports that the DU2 is congested. Alternatively, the DU2 sets the bearer-level data request quantity to zero in the DDDS, and carries the information that the bearer-level data request quantity is set to zero in the DDDS, and reports the DU2 congestion to the main CU1 through the Xn interface.

The primary CU1 side knows that the secondary DU2 is congested, and the suspension continues to send downlink data to the secondary DU2; meanwhile, the subsequent data packet is transmitted through the other side primary DU1. The UE receives data through the primary DU1.

As shown in FIG. 5, the LTE-NR dual connection between different CUs, the data is split between the LTE base station and the NR base station by using the Xn interface in the primary CU1, and the terminal receives the downlink data of the offload from the LTE base station and the NR base station through the dual connection, respectively. Reorder processing.

When the secondary LTE base station detects the downlink congestion by using the link detection, it calculates the maximum data packet information that the secondary LTE base station can currently process, and uses the SN of the data packet as the congestion SN; carries the congestion SN in the DDDS, and passes The Xn interface reports the secondary LTE base station congestion to the primary CU1. Alternatively, the secondary LTE base station sets the bearer-level data request quantity to zero in the DDDS, and carries the information that the bearer-level data request quantity is set to zero in the DDDS, and reports the secondary LTE base station congestion to the primary CU1 through the Xn interface.

The primary CU1 side knows that the secondary LTE base station is congested, and suspends the transmission of the downlink data to the secondary LTE base station; meanwhile, the subsequent data packet is transmitted through the other side primary DU1. The UE receives data through the primary DU1.

According to the air interface link congestion feedback method of the embodiment of the present disclosure, when the CU and the DU are separated, when the DU side link is congested, the CU side can quickly change the offload policy or perform link conversion according to the congestion indication information reported by the DU. In order to improve data transmission efficiency, meet the technical requirements of 5G high-speed transmission and fast switching.

As shown in FIG. 7, an embodiment of the present disclosure provides an air interface link congestion feedback apparatus, and the apparatus may include a DU 21 and a CU 22.

The DU 21 may be configured to perform congestion detection on the downlink; if the downlink congestion is detected, the congestion indication information is generated; and the congestion indication information is reported to the CU 22.

In the embodiment of the present disclosure, the DU 21 may perform congestion detection on the downlink based on at least one of the following information: a CQI measurement report reported by the terminal, an SRS measurement result, a downlink buffer data transmission delay, and a number of RLC retransmissions, The number of HARQ retransmissions.

In the embodiment of the present disclosure, the DU 21 may be further configured to: if the downlink congestion is detected, calculate the congestion SN and use the congestion SN as the congestion indication information, or set the bearer level data request amount to zero and set The bearer level data request amount of zero is used as the congestion indication information.

In the embodiment of the present disclosure, the DU 21 may calculate the congested SN based on at least one of the following information: a data buffer condition of the DU, status report information fed back by the user terminal, an air interface link condition, HARQ information of the MAC, and RLC. ARQ information.

In the embodiment of the present disclosure, the DU 21 may be further configured to calculate a sequence number of a maximum data packet that the DU 21 can currently process, and use a sequence number of the data packet as a congestion sequence number.

The CU 22 may be configured to acquire congestion indication information reported by the DU 21, and perform link adjustment according to the congestion indication information.

In the embodiment of the present disclosure, the DU21 reports the congestion indication information to the CU 22 through the DDDS. After the CU 22 acquires the congestion indication information reported by the DU 21, the CU 22 performs link adjustment according to the congestion indication information.

In order to better illustrate the embodiments of the present disclosure, the processing sequence of the air interface link congestion feedback in different application scenarios will be described below with reference to FIG. 8 to FIG. 11 .

Figure 8 shows the congestion processing in the case where data is shunted between two DUs of the same CU. The data is shunted between the two stations in the CU through two F1 interfaces, and the terminal receives the downlink data of the shunt through two DUs. Perform reordering processing.

Figure 9 shows the congestion processing of data in the case of duplication transmission between two DUs of the same CU. The data is duplicated between the two stations in the CU through two F1 interfaces, and the terminal receives the same downlink data through two DUs. And repeat the packet processing.

Figure 10 shows the congestion processing in the case of NR-NR dual connectivity between different CUs. The data is offloaded between the two NR base stations by the primary CU1 through the Xn interface, and the terminal receives the downlink data of the offload from the two NR base stations through the dual connection. And reordering processing.

FIG. 11 shows congestion processing in the case of LTE-NR dual connectivity between different CUs. The data is split between the LTE base station and the NR base station by the primary CU1 through the Xn interface, and the terminal receives the offload from the LTE base station and the NR base station through the dual connection, respectively. Downstream data and reordering processing.

When detecting the downlink congestion by the link detection, the secondary LTE base station calculates the maximum data packet information that the secondary LTE base station can currently process, and uses the SN of the data packet as the congestion SN; carries the congestion SN in the DDDS, and passes the Xn The interface reports the congestion of the secondary LTE base station to the primary CU1. Alternatively, the secondary LTE base station sets the bearer-level data request quantity to zero in the DDDS, and carries the information that the bearer-level data request quantity is set to zero in the DDDS, and reports the secondary LTE base station congestion to the primary CU1 through the Xn interface.

In the case of the air interface link congestion feedback device of the embodiment of the present disclosure, when the CU and the DU are separated, the CU side can quickly change the traffic off policy or perform link conversion according to the congestion indication information reported by the DU. Thereby improving data transmission efficiency, meeting the technical requirements of 5G high-speed transmission and fast switching.

As shown in FIG. 12, an embodiment of the present disclosure provides an air interface link congestion feedback device, where the device may include: a memory 31, a processor 32, and is stored on the memory 31 and operable on the processor 32. The air interface link congestion feedback procedure is used to implement steps S11 to S13 of the air interface link congestion feedback method described below when the air interface link congestion feedback procedure is executed by the processor 32.

At step S11, the DU performs congestion detection on the downlink.

When the air interface link congestion feedback procedure is executed by the processor 32, the method further includes the following steps of implementing the air interface link congestion feedback method: the DU performs downlink on the downlink based on at least one of the following information Congestion detection: CQI measurement report, SRS measurement result, downlink buffer data transmission delay, RLC retransmission times, and HARQ retransmission times reported by the terminal.

When the air interface link congestion feedback procedure is executed by the processor 32, the method further includes the following steps of implementing the air interface link congestion feedback method: if downlink congestion is detected, calculating a congestion serial number and The congestion sequence number is used as the congestion indication information, or the bearer level data request amount is set to zero and the bearer level data application amount set to zero is used as the congestion indication information.

When the air interface link congestion feedback procedure is executed by the processor 32, the method further includes the step of implementing the air interface link congestion feedback method: calculating the congestion serial number based on at least one of the following information: DU The data buffering situation, the status report information fed back by the user terminal, the air interface link status, the HARQ information of the MAC, and the ARQ information of the RLC.

When the air interface link congestion feedback procedure is executed by the processor 32, the method further includes: performing the following steps of the air interface link congestion feedback method: calculating a sequence number of a maximum data packet that the DU can currently process, and The serial number of the packet is taken as the congestion sequence number.

An embodiment of the present disclosure provides a computer readable storage medium, where the air interface link congestion feedback program is stored, and the air interface link congestion feedback program is used by the processor to implement the foregoing embodiment. The steps of the air interface link congestion feedback method.

The computer readable storage medium of the embodiment of the present disclosure, when the CU and the DU are separated, when the DU side link is congested, the CU side can quickly change the offload policy or perform link conversion according to the congestion indication information reported by the DU, thereby Improve data transmission efficiency, meet the technical requirements of 5G high-speed transmission and fast switching.

It should be noted that the foregoing device embodiment and the method embodiment are in the same concept, and the specific implementation process is described in detail in the method embodiment, and the technical features in the method embodiment are applicable in the device embodiment, and details are not described herein again.

Through the description of the above embodiments, those skilled in the art can clearly understand that the foregoing embodiment method can be implemented by means of software plus a necessary general hardware platform, and can also be implemented by hardware, but in many cases, the former is A better implementation. Based on such understanding, portions of the technical solutions of the present disclosure that contribute substantially or to the prior art may be embodied in the form of a software product stored in a storage medium (eg, ROM/RAM, disk, The optical disc includes instructions for causing a terminal device (e.g., a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the methods described in various embodiments of the present disclosure.

The embodiments described above with reference to the drawings are not intended to limit the scope of the claims. Various modifications may be made by those skilled in the art without departing from the scope and spirit of the disclosure. For example, the features of one embodiment can be used in another embodiment. Any modifications, equivalent substitutions and improvements made within the inventive concept of the present disclosure are intended to be within the scope of the present disclosure.

Claims

An air interface link congestion feedback method includes the following steps:

The distribution unit DU performs congestion detection on the downlink;

Generating congestion indication information when downlink congestion is detected;

The congestion indication information is reported to the central unit CU, so that the CU performs link adjustment according to the congestion indication information.
The method of claim 1, wherein the DU performs congestion detection on the downlink based on at least one of the following information:

The channel quality indicator CQI measurement report reported by the terminal, the sounding reference signal SRS measurement result, the downlink buffer data transmission delay, the number of radio link control RLC retransmissions, and the hybrid automatic repeat request HARQ retransmission times.
The method of claim 1, wherein the step of generating congestion indication information in the event that downlink congestion is detected comprises the steps of:

In the case where downlink congestion is detected, the congestion sequence number is calculated and the congestion sequence number is used as congestion indication information.
The method of claim 1, wherein the step of generating congestion indication information in the event that downlink congestion is detected comprises the steps of:

When the downlink congestion is detected, the bearer level data request quantity is set to zero and the bearer level data application quantity set to zero is used as the congestion indication information, where the bearer level data application quantity is set to zero. The number of times is at least 1.
The method of claim 3, wherein the congestion sequence number is calculated based on at least one of the following information:

The data buffering situation of the DU, the status report information fed back by the user terminal, the air interface link condition, the HARQ information of the medium access control MAC, and the automatic retransmission request ARQ information of the RLC.
The method of claim 3 wherein said step of calculating a congestion sequence number comprises the steps of:

The serial number of the largest data packet that the DU can currently process is calculated, and the serial number of the data packet is used as the congestion serial number.
An air interface link congestion feedback device includes:

a distribution unit (DU) configured to perform congestion detection on the downlink, generate congestion indication information when downlink congestion is detected, and report the congestion indication information to the central unit CU;

The centralized unit CU is configured to acquire congestion indication information reported by the DU, and perform link adjustment according to the congestion indication information.
The apparatus of claim 7, wherein the DU performs congestion detection on the downlink based on at least one of the following information:

The channel quality indicator CQI measurement report reported by the terminal, the sounding reference signal SRS measurement result, the downlink buffer data transmission delay, the radio link control RLC retransmission times, and the hybrid automatic retransmission request HARQ retransmission times.
The apparatus according to claim 7, wherein said DU is further arranged to calculate a congestion sequence number and use the congestion sequence number as congestion indication information in the case where downlink congestion is detected.
The apparatus according to claim 7, wherein said DU is further configured to set a bearer level data request amount to zero and to set a bearer level data request amount of zero as congestion in the case where downlink congestion is detected. The indication information, wherein the number of times the bearer level data request quantity is set to zero is at least 1.
The apparatus of claim 9, wherein the DU calculates the congestion sequence number based on at least one of the following information:

The data buffering situation of the DU, the status report information fed back by the user terminal, the air interface link condition, the HARQ information of the medium access control MAC, and the automatic retransmission request ARQ information of the RLC.
The apparatus of claim 9, wherein the DU is further configured to calculate a sequence number of a maximum data packet that the DU can currently process, and use a sequence number of the data packet as a congestion sequence number.
An air interface link congestion feedback device includes: a memory, a processor, and an air interface link congestion feedback program stored on the memory and operable on the processor, where the air interface link congestion feedback procedure is The step of implementing the air interface link congestion feedback method according to any one of claims 1 to 6 when the processor is executed.
A computer readable storage medium storing an air interface link congestion feedback program, wherein the air interface link congestion feedback program is executed by a processor to implement any one of claims 1 to 6 The steps of the air interface link congestion feedback method.