WO2013173959A1

WO2013173959A1 - Transmission method and rlc layer receiving entity

Info

Publication number: WO2013173959A1
Application number: PCT/CN2012/075818
Authority: WO
Inventors: 杨莎
Original assignee: 华为技术有限公司
Priority date: 2012-05-21
Filing date: 2012-05-21
Publication date: 2013-11-28
Also published as: CN103563281A

Abstract

Embodiments of the present invention provide a transmission method and an RLC layer receiving entity. In the embodiments of the present invention, when a T_Reordering timer times out, an RLC layer receiving entity constructs an RLC layer status report, and sends the RLC layer status report, a time interval between the time when the RLC layer receiving entity sends the RLC layer status report and the time when the RLC layer receiving entity sends another RLC layer status report being not limited by a T_StatusProhibit timer, so that a retransmission delay of the RLC layer receiving entity is equal to a duration of the T_Reordering timer, and is far shorter than the retransmission delay of an existing ARQ mechanism. In this way, the retransmission delay is reduced, thereby improving the transmission performance of a communication system.

Description

Transmission method and RLC layer receiving entity

Technical field

The present invention relates to communication technologies, and in particular, to a transmission method and a Radio Link Control (RLC) layer receiving entity. Background technique

In a communication system such as a Long Term Evolution (LTE) system, in order to ensure the reliability of data transmission, an automatic repeat request (Automatic Repeat-reQuest) can be adopted at the Radio Link Control (RLC) layer. ARQ) mechanism.

However, in the scenario where the air interface signal quality is poor, the retransmission delay of the existing ARQ mechanism is large. Summary of the invention

The present invention provides a transmission method and an RLC layer receiving entity for reducing retransmission delay, thereby improving transmission performance of a communication system.

In one aspect, a transmission method is provided, including:

The RLC layer receiving entity receives the data packet;

And when the RLC layer receiving entity detects that the data packet is out of order, starting a T_Reordering timer;

When the T_Reordering timer expires, the RLC layer receiving entity constructs a status report of the RLC layer, and sends a status report of the RLC layer; wherein, the interval between the time when the RLC layer receives the status report of the entity is not Limited by the T_StatusProhibit timer.

Another aspect provides an RLC layer receiving entity, including:

a receiving unit, configured to receive a data packet;

a processing unit, configured to detect whether the data packet is out of order, and when detecting that the data packet is out of order, start a T_Reordering timer;

a sending unit, configured to: when the T_Reordering timer expires, construct a status report of the RLC layer, and send a status report of the RLC layer; where the sending unit sends the RLC The interval between the time when the status of the layer is reported and the time when the transmitting unit sends the status report of the other RLC layer is not limited by the T_StatusProhibit timer.

According to the foregoing technical solution, when the T_Reordering timer expires, the RLC layer receiving entity constructs a status report of the RLC layer, and sends a status report of the RLC layer, where the RLC layer receiving entity sends the RLC. The interval between the time reported by the layer and the time when the RLC layer receiving entity sends the status report of the other RLC layer is not limited by the T_StatusProhibit timer, so that the retransmission delay of the RLC layer receiving entity is equal to the duration of the T_Reordering timer. , which is much smaller than the retransmission delay of the existing ARQ mechanism, so that the retransmission delay is reduced, thereby improving the transmission performance of the communication system. BRIEF DESCRIPTION OF THE DRAWINGS In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief description of the drawings used in the embodiments or the prior art description will be briefly described below. The drawings are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive labor.

FIG. 1 is a schematic flowchart of a transmission method according to an embodiment of the present invention;

2 is a schematic flowchart of a transmission method according to another embodiment of the present invention;

FIG. 3 is a schematic structural diagram of an RLC layer receiving entity according to another embodiment of the present invention. The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. The embodiments are a part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

The technical solution of the present invention can be applied to various communication systems, such as: Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS) system, and code division multiple access (Code) Division Multiple Access, CDMA) system, CDMA2000 system, wideband code division Wideband Code Division Multiple Access (WCDMA) system, Long Term Evolution (LTE) system or World Interoperability for Microwave Access (WiMAX) system.

Each entity of each RLC layer can be configured by a Radio Resource Control (RRC) layer and operates in three data transmission modes: Transparent Mode (TM) and Unacknowledged Mode (Unacknowledged Mode). UM) and Acknowledged Mode (AM). The ARQ mechanism in the AM sends a Status Report through the RLC layer receiving entity, so that the peer entity determines which packets are acknowledged and received, and which packets need to be retransmitted according to the status report, thereby ensuring data transmission. reliability.

In the existing ARQ mechanism, the triggering process for the status report in the AM mode is affected by two timers, one is a reordering (T_Reordering) timer, and the other is a status reporting inhibit (T_StatusProhibit) timer. If the RLC layer receiving entity detects the data packet, that is, the Protocol Data Unit (PDU) does not arrive in order, the T_Reordering timer is started immediately. When the T_Reordering timer expires, the RLC layer receives the entity update. The data receiving window (ie, the variable VR (MS), which is used to identify the cutoff position of the constructed status report, that is, the sequence number (SN) of the PDU), and constructs a status report according to the updated data receiving window, but cannot immediately send. The RLC layer receiving entity needs to wait for the T_StatusProhibit timer to time out before sending the constructed status report. In this way, the retransmission delay of the RLC layer receiving entity may be equal to the sum of the duration of the T_Reordering timer and the duration of the T_StatusProhibit timer, and the retransmission delay is large, so that the transmission performance of the communication system is degraded. The duration of the T_Reordering timer and the duration of the T_StatusProhibit timer can be set freely by various vendors. The effect is different depending on the configuration of each vendor.

FIG. 1 is a schematic flowchart of a transmission method according to an embodiment of the present invention. As shown in FIG. 1, the transmission method in this embodiment may include:

101. The RLC layer receiving entity receives the data packet.

102. When the RLC layer receiving entity detects that the data packet is out of order, start a T_Reordering timer.

103. When the T_Reordering timer expires, the RLC layer receiving entity constructs a status report of the RLC layer, and sending a status report of the RLC layer; wherein, the time when the RLC layer receiving entity sends the status report of the RLC layer and the time when the RLC layer receiving entity sends status reports of other RLC layers The interval between them is not limited by the T_StatusProhibit timer.

Optionally, in an optional embodiment of this embodiment, when the T_Reordering timer expires, the RLC layer receives an entity update data receiving window (ie, a variable VR(MS)), and constructs a status report according to the updated data receiving window. , and immediately send the constructed status report without being limited by the T_StatusProhibit timer. In this way, the retransmission delay of the receiving entity of the RLC layer is equal to the duration of the T_Reordering timer, which is much smaller than the retransmission delay of the existing ARQ mechanism, and the maximum duration of the T_StatusProhibit timer is saved, which can effectively improve the transmission performance of the communication system.

In this embodiment, when the T_Reordering timer expires, the RLC layer receiving entity constructs a status report of the RLC layer, and sends a status report of the RLC layer, where the RLC layer receiving entity sends the status report of the RLC layer. The interval between the time and the time when the RLC layer receiving entity sends the status report of the other RLC layer is not limited by the T_StatusProhibit timer, so that the retransmission delay of the RLC layer receiving entity is equal to the duration of the T_Reordering timer, which is much smaller than the current time. The retransmission delay of some ARQ mechanisms reduces the retransmission delay, thereby improving the transmission performance of the communication system.

In another embodiment of the present invention, the duration of the T_StatusProhibit timer is greater than zero. It should be noted that in the case where the duration of the T_StatusProhibit timer is greater than 0, the AM mode of the RLC layer is valid.

It can be understood that, according to the method provided in this embodiment, when the AM mode of the RLC layer is valid, regardless of the duration of the T_StatusProhibit timer, the RLC layer receiving entity immediately sends a status report when the T_Reordering timer expires, thereby ensuring that the status report is ensured. Reduce retransmission delay and improve communication system transmission performance.

Optionally, in another embodiment of the present invention, as shown in FIG. 2, after 103, the RLC layer receiving entity may further perform the following steps:

201. The RLC layer receiving entity restarts the T_StatusProhibit timer.

That is, after transmitting the status of the RLC layer, the above-mentioned D_313 5 1"01^1^ timer is restarted, that is, it is not allowed to be used during the operation of the D_313 5 1"01^1^ timer. The status report of the RLC layer is sent until the T StatusProhibit timer expires before the status report of the RLC layer is sent. It should be noted that the RLC layer receiving entity restarts the T-StatusProhibit timer. Processed in the same way as the technology, that is, the implementation of the embodiment is related to the prior art

The restart process of the T_StatusProhibit timer can be combined to reduce the frequency of the RLC layer receiving the status report of the RLC layer, so that the air interface resources are saved, and details are not described herein.

It should be noted that, for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations, but those skilled in the art should understand that the present invention is not limited by the described action sequence. Because certain steps may be performed in other sequences or concurrently in accordance with the present invention. In addition, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

In the above embodiments, the descriptions of the various embodiments are different, and the parts that are not detailed in a certain embodiment can be referred to the related descriptions of other embodiments.

FIG. 3 is a schematic structural diagram of an RLC layer receiving entity according to another embodiment of the present invention. As shown in FIG. 3, the RLC layer receiving entity in this embodiment may include a receiving unit 31, a processing unit 32, and a sending unit 33. The receiving unit 31 is configured to receive a data packet; the processing unit 32 is configured to detect whether the data packet is out of order, and when detecting that the data packet is out of order, start a T_Reordering timer; and the sending unit 33 is configured to When the T_Reordering timer expires, the status of the RLC layer is constructed, and the status of the RLC layer is sent, wherein the interval between the sending units 33 is not limited by the T_StatusProhibit timer.

In an optional embodiment of the present embodiment, the RLC layer receiving entity provided in this embodiment may further include the T_Reordering timer and the T_Review timer. In this embodiment, when the processing unit starts the T_Reordering timer. When the timeout occurs, the sending unit 33 constructs a status report of the RLC layer, and immediately transmits a status report of the RLC layer, where

The limitation of the timer is such that the retransmission delay of the RLC layer receiving entity is equal to the duration of the T_Reordering timer, which is much smaller than the retransmission delay of the existing ARQ mechanism, so that the retransmission delay is reduced, thereby improving the transmission of the communication system. performance.

In another embodiment of the present invention, the duration of the T_StatusProhibit timer is greater than zero. It should be noted that in the case where the duration of the T StatusProhibit timer is greater than 0, The AM mode of the RLC layer is valid.

Optionally, in another embodiment of the present invention, after the sending unit 33 sends the status report of the RLC layer, the processing unit 32 may also restart the T_StatusPmhibit timer, that is, the sending is not allowed during the running of the T_StatusProhibit timer. The unit 33 then sends the status of the RLC layer, until the T_StatusProhibit timer expires before the status 4 of the RLC layer is retransmitted. It should be noted that the processing unit 32 restarts the T_StatusProhibit timer in the same manner as the prior art, that is, the implementation of the embodiment can be combined with the restart process of the T_StatusProhibit timer in the prior art, thereby reducing the subsequent RLC. The layer receives the frequency of the status of the RLC layer, so that the air interface resources are saved, and details are not described herein.

A person skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working process of the system, the device and the unit described above can refer to the corresponding process in the foregoing method embodiment, and details are not described herein again.

In the several embodiments provided herein, it should be understood that the disclosed systems, devices, and methods may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not executed. In addition, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be electrical, mechanical or otherwise.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of hardware plus software functional units.

The above-described integrated unit implemented in the form of a software functional unit can be stored in a computer readable storage medium. The above software functional unit is stored in a storage medium and includes a plurality of instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) Some of the steps of the method described in various embodiments of the present invention are performed. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like, which can store program code. .

It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced. The modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

claims

1. A transmission method, characterized by including:

The radio link control RLC layer receiving entity receives the data packet;

When the RLC layer receiving entity detects that the data packet is out of order, it starts the T_Reordering timer;

When the T_Reordering timer times out, the RLC layer receiving entity constructs a status report of the RLC layer and sends the status report of the RLC layer; wherein, the interval between the times when the RLC layer receives status reports of the entity is not Limited by the T_StatusProhibit timer.

2. The method according to claim 1, characterized in that the duration of the T_StatusProhibit timer is greater than 0.

3. A radio link control RLC layer receiving entity, characterized by including:

Receiving unit, used to receive data packets;

A processing unit, used to detect whether the data packet is out of order, and when detecting that the data packet is out of order, start the T_Reordering timer; and

A sending unit, configured to construct a status report of the RLC layer when the T_Reordering timer times out, and send the status report of the RLC layer; wherein, the time when the sending unit sends the status report of the RLC layer is the same as the time of sending the status report of the RLC layer. The interval between the times when the sending unit sends status reports of other RLC layers is not limited by the T_StatusProhibit timer.

4. The RLC layer receiving entity according to claim 3, characterized in that the RLC layer receiving entity further includes: the T_Reordering timer and the T_StatusProhibit timer.

5. The RLC layer receiving entity according to claim 3 or 4, characterized in that the duration of the T StatusProhibit timer is greater than 0.