CN100428663C - A method, device and system for detecting data loss - Google Patents

Abstract

The invention relates to a method, device and system for detecting the number of data loss in the technical field of communication. The method includes: the user equipment side uses the transmission sequence number TSN to indicate the sequence number of the first MAC-d PDU encapsulated in the MAC-es PDU, and sends the data carrying the TSN to the base station; after the base station receives the data, the calculation continues The process difference of receiving data twice, judge whether there is data loss according to the process difference; Calculate the number of lost MAC-d PDUs. In the present invention, by using TSN to indicate the serial number of the first MAC-d PDU encapsulated by the MAC-es PDU, the transmission situation of the last TTI can be known, and the number of lost MAC-d PDUs can be detected. Therefore, through corresponding processing, the number of retransmissions is reduced, and the system throughput and transmission success rate can be improved.

Description

A method, device and system for detecting data loss

technical field

The invention relates to the technical field of communications, in particular to a method, device and system for detecting data loss numbers.

Background technique

3GPP (Third Generation Partnership Project) organization began to formulate WCDMA system uplink data transmission enhancement technology HSUPA (High Speed Uplink Packet Data Access) in 2004. The HSUPA system uses HARQ (composite retransmission) technology and NodeB fast scheduling technology And the uplink 2ms short frame technology greatly improves the throughput rate of uplink user data. The peak rate of the air interface can reach 5.76Mbps, and it also greatly improves the uplink capacity of the system.

The HSUPA system does not involve entities above the RLC (Radio Link Control) layer of the WCDMA system. It adds MAC (Media Access Control) entities and physical layer channels. The protocol model of the data transmission process is shown in Figure 1:

After the data of the logical channel DTCHs (Dedicated Traffic Channel)/DCCHs (Dedicated Control Channel) on the UE side is processed by the MAC-d and MAC-es/e entities, it is carried on the E-DCH (Enhanced Dedicated Channel) transport channel and mapped On the uplink physical channel E-DPDCHs, it is sent to the NodeB through the air interface. Among them, the MAC-es/e entity is a newly added functional entity after the introduction of HSUPA technology. It is mainly responsible for multiplexing MAC-d PDU (MAC-d protocol data unit) data from different MAC-d flow data streams to generate MAC-e After the PDU data block is transmitted, each TTI (transmission time interval) can only transmit 1 MAC-e PDU data block.

The structure of the MAC-es/e entity on the UE side is shown in Figure 2: the functional module "E-TFC Selection" of the MAC-es/e entity is used to select the transmission format and determine the size of the MAC-ePDU that can be transmitted within one TTI. Transfer according to the block size allowed for transfer. The "Multiplexing and TSNsetting" function module is used to multiplex MAC-d PDU data packets from different MAC-d flow data flows to generate MAC-e PDU data blocks. Then transmit the MAC-e PDU data block to the functional module HARQ (stop and wait for retransmission entity). The HARQ function module assigns a process to the TTI data block MAC-e PDU, and uses the downlink synchronous ACK/NACK process transmission method for data transmission.

The prior art scheme defines the format of the MAC-e PDU data block, as shown in Figure 3: wherein DDI (data description indication), N are header information of MAC-e PDU, wherein DDI includes: logical channel ID, MACd Flow ID, RLC PDU size and other information; N indicates the number of RLC PDUs contained in a MAC-es PDU. TSN indicates the transmission sequence number of the logical channel MAC-es PDU on the E-DCH transmission channel. MAC-e PDUs are sent on every TTI boundary. Each MAC-e PDU may contain multiple MAC-es PDUs. Each MAC-es PDU corresponds to a set of DDI, N, TSN and is composed of multiple MAC-d PDUs. Described MAC-d PDU is equal to RLC PDU, refers to the data unit from RLC layer. Assuming that the MAC-e PDU contains only one MAC-es PDU, that is, there is only one set of DDI, N, and TSN, then each time after the MAC-e PDU is assembled and sent, the TSN is incremented with a step size of 1, starting with (0. ..63) is the cycle period.

After receiving the MAC-e PDU uploaded by the UE on the NodeB side, the encapsulated MAC-esPDU is split and sent to the MACes entity of the RNC according to the MACd flow, and the reordering queue distribution function block of the MACes entity of the RNC will come from the same The data of the MACd flow is distributed to different reordering entity/combining functional entity queues according to the logical channel ID. This ensures that the MAC-es PDUs in each reordering entity/combining functional entity queue have the same MACd Flow ID and logical channel ID.

Utilize TSN and CFN (continuous frame number) and SubFn (subframe number) in the above-mentioned process, can get rid of the data packet that sends repeatedly, and continuous MAC-es PDU is split into RLC PDU and sends in the data packet splitting entity, It is then passed to the RLC layer of the RNC.

As can be seen from the above description, in the prior art, by adding TSN instructions, the reordering entity/combining function entity of the RNC realizes the sorting of out-of-order MAC-es PDUs, although it can be in a certain receiving window under the cooperation of CFN and SubFn Achieving correct sorting within ranges, but in the presence of data loss, it is impossible to detect the amount of data loss.

Contents of the invention

The object of the present invention is to provide a method, device and system for detecting the number of data loss.

The purpose of the present invention is achieved through the following technical solutions:

A method of detecting data loss data comprising:

A. The user equipment side uses the transmission sequence number TSN to represent the first MAC-d PDU sequence number encapsulated in the MAC-es protocol data unit PDU, and sends the data carrying the TSN to the base station;

B. After the base station receives the data, it calculates the process difference of receiving data twice in a row, and judges whether there is data loss according to the process difference;

C. When the process difference is 2, calculate the number of lost MAC-d PDUs according to the TSN values of the data received twice before and after and the number of MAC-d PDUs in the sent data.

The representation method of TSN in the step A is:

TSN _i+1 = mod(TSN _i +N _i +1, 64),

Where TSN _i+1 is the serial number of the first MAC-d PDU in the data sent by the i+1 process;

TSN _i is the sequence number of the first MAC-d PDU in the data sent by process i;

Ni is the number of MAC-d PDUs sent by process i;

mod means to take the modulo operation on the number in the subsequent expansion.

The process difference calculation method is:

Process difference = (later data reception time - first data reception time)/transmission time interval length.

In the step B, when the calculation process difference is 1, it indicates that the data transmission process is continuous and there is no data loss.

The method for calculating the number of lost MAC-d PDUs in the step C further includes:

TSN _x+i = mod(TSNx ₊ N _x +N _x+i-1 , 64),

Where TSN _x+i is the serial number of the first MAC-d PDU in the data received by the subsequent x+i process;

TSN _x is the sequence number of the first MAC-d PDU in the data received by the previous x process;

N _x is the number of MAC-d PDUs received by the previous x process;

N _x+i-1 is the number of lost MAC-d PDUs.

A system for detecting the number of data loss, including a user equipment side and a base station side, a transmission sequence number setting module is set on the user equipment side, and is used to set the MAC-es protocol data unit PDU to represent the first packet encapsulated in the MAC-es PDU TSN value of a MAC-d PDU sequence number;

Set on the base station side:

The process difference calculation module is used to record the time of receiving data each time, and calculates the process difference of receiving data twice in a row according to the time;

A data loss judgment module is used to judge whether the process is continuous according to the calculation result of the process difference calculation module, so as to determine whether there is data loss;

The data loss number calculation module is used to receive the judgment result of the data loss judgment module, and when the process difference is 2, calculate the loss according to the TSN value of the data received twice before and after and the number of MAC-dPDUs in the sent data The number of MAC-d PDUs.

A base station, comprising:

The process difference calculation module is used to record the time of receiving data each time, and calculates the process difference of receiving data twice in a row according to the time;

A data loss judgment module is used to judge whether the process is continuous according to the calculation result of the process difference calculation module, so as to determine whether there is data loss;

The data loss number calculation module is used to receive the judgment result of the data loss judgment module, and when the process difference is 2, calculate the loss according to the TSN value of the data received twice before and after and the number of MAC-dPDUs in the sent data The number of MAC-d PDUs.

As can be seen from the technical solution provided by the present invention above, the present invention can know the transmission situation of the last TTI and detect the lost MAC-d PDU by utilizing the sequence number of the first MAC-d PDU encapsulated by the TSN to indicate the MAC-es PDU. Number of PDUs. Therefore, through corresponding processing, the number of retransmissions is reduced, and the system throughput and transmission success rate can be improved.

Description of drawings

Fig. 1 is the schematic diagram of prior art HSUPA system data transmission process protocol model;

FIG. 2 is a schematic diagram of a UE-side MAC-es/e entity structure in the prior art;

Fig. 3 is the format of prior art MAC-e PDU data block;

Fig. 4 is a schematic diagram of a module of an embodiment of the system of the present invention;

Fig. 5 is a flow chart of the operation of an embodiment of the method of the present invention;

FIG. 6 is a schematic diagram of assembling a MAC-e PDU according to an embodiment of the UE side of the present invention.

Detailed ways

The core idea of the present invention is to provide a method and system for detecting the number of data loss, using TSN to represent the initial MAC-d PDU serial number transmitted in the MAC-e PDU, combined with the process ID of the transmission, the number of data loss can be detected, Thereby improving system throughput and transmission success rate.

The present invention provides a system for detecting the number of data loss. The module diagram of an embodiment of the system is shown in Figure 4. On the UE side, a transmission sequence number setting module is provided for setting the TSN value for the MAC-es PDU. , used to indicate the sequence number of the first MAC-d PDU encapsulated in the MAC-es PDU.

A process difference calculation module, a data loss judgment module, and a data loss number calculation module are set on the NodeB side;

The process difference calculation module is used to record the time of receiving data each time, and calculates the process difference of receiving data twice in a row according to the time, which can be specifically expressed as:

Process difference = (later data reception time - first data reception time)/transmission time interval length.

The data loss judgment module is used to judge whether the process is continuous according to the calculation result of the process difference calculation module, so as to determine whether there is data loss. Only when the process difference is 1, the process can be determined to be continuous, otherwise, there is data loss.

The data loss number calculation module is used to receive the judgment result of the data loss judgment module, when the process difference is 2, according to the TSN value of the data received twice before and after and the number of MAC-d PDUs in the data sent Calculate the number of lost MAC-d PDUs.

The present invention provides a method for detecting the number of lost data, using TSN to represent the sequence number of the first MAC-d PDU encapsulated in the corresponding MAC-esPDU, and determining the transmission situation of the last TTI according to the sequence number, thereby detecting the number of lost data . An embodiment of the operation process is shown in Figure 5, including the following steps:

Step 1: When the MACes entity on the UE side is performing a packet operation, the transmission sequence number setting module sets the TSN value for the encapsulated data packet to represent the sequence number of the first MAC-d PDU encapsulated, and transmits it to the NodeB ;

The grouping process is shown in Figure 6. The TSN is independently maintained by the logical channel, and the TSN calculation corresponding to a certain logical channel is as follows:

Assuming that a process applies for N _i MAC-d PDU data packets to the logical channel for MAC-es PDU assembly, and the calculated TSN is TSN _i , then the TSN calculation method for the data application of the logical channel in the next TTI is as follows:

TSN _i+1 = mod(TSN _i +N _i +1, 64),

Where TSN _i is the TSN information calculated when a HARQ process applies for a MAC-d PDU to a logical channel for the i-th time to assemble a MAC-es PDU, indicating the sequence number of the first MAC-dPDU encapsulated by the MACes, and its initial The value is 0. For example, if it is the first time to apply for 10 MAC-d PDU data packets from this logical channel, then TSN ₀ is set to 0, N ₀ is set to 10, and the TSN ₁ that needs to be allocated during the next data application is calculated = mod(10 +1, 64)=11, indicating that the serial number of the MAC-d PDU of this transmission is 11, and 10 MAC-dPDUs have been transmitted before;

N _i is the number of MAC-dPDUs used to assemble MAC-es PDUs when a process applies to the logical channel for the ith time;

Step 2: after the NodeB receives the data sent by the UE, the process difference calculation module calculates the process difference;

Every time NodeB receives data, the transmission sequence number setting module will record the current receiving time, compare the current receiving data time with the previous receiving data time, and calculate the difference between the two receiving data processes. For example: NodeB receives MAC-e PDU0 from UE at T _j and MAC-e PDU1 at T _k respectively, during which no other MAC-e PDUs are received. Corresponding to the same DDI, there are corresponding MACesPdu0 and MACes Pdu1, and the process difference between the two sending packets is:

i=( _Tj - _Tk )/TTIlength;

Wherein, TTIlength represents the TTI length.

Step 3: the data loss judging module judges whether there is data loss according to the process difference calculation result, and transmits the judgment result to the data loss calculation module;

If the process difference is 1, it means that the data transmission is continuous and there is no lost data; if the process difference is greater than 1, it means that the data transmitted by i-1 processes before can not be received correctly and wait for retransmission;

Step 4: when the i value is 2, it means that the data sent by the process HARQ (i-1) is not correctly received by the NodeB, then the data loss number calculation module calculates the MAC-d PDU number lost by the process;

Assuming that the MAC-es PDU header information corresponding to the same DDI of the process x before the process with a difference of i processes from the current process is TSN _x , N _x , then

TSN _x+i = mod(TSN _x +N _x +N _x+i-1 , 64),

Where N _x+i-1 represents the number of MAC-d PDUs sent by process HARQ _x+i-1 , that is, the number of MAC-d PDUs not received correctly.

In summary, the present invention can know the transmission situation of the last TTI and detect the number of lost MAC-d PDUs by using the TSN to indicate the sequence number of the first MAC-dPDU encapsulated by the MAC-es PDU. Therefore, through corresponding processing, the number of retransmissions is reduced, and the system throughput and transmission success rate can be improved.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (7)

1. A method for detecting data loss, comprising: A, the base station receives the data carrying the transmission sequence number TSN sent by the user equipment side, and the TSN represents the first MAC-d PDU sequence number encapsulated in the MAC-es protocol data unit PDU; B. After the base station receives the data, it calculates the process difference of receiving data twice in a row, and judges whether there is data loss according to the process difference; C. When the process difference is 2, calculate the number of lost MAC-d PDUs according to the TSN values of the data received twice before and after and the number of MAC-d PDUs in the sent data. 2. A method for detecting the number of data loss as claimed in claim 1, characterized in that, the expression method of TSN in the step A is: TSN _i+1 = mod(TSN _i +N _i +1, 64), Where TSN _i+1 is the serial number of the first MAC-d PDU in the data sent by the i+1 process; TSN _i is the sequence number of the first MAC-d PDU in the data sent by process i; Ni is the number of MAC-d PDUs sent by process i; mod means to take the modulo operation on the number in the subsequent expansion. 3. A method for detecting data loss as claimed in claim 1, wherein the method for calculating the process difference is: Process difference = (later data reception time - first data reception time)/transmission time interval length. 4. The method for detecting the number of data loss according to claim 1, characterized in that, in the step B, when the calculation process difference is 1, it indicates that the data transmission process is continuous and there is no data loss. 5. A method for detecting data loss as claimed in claim 1, wherein the method for calculating the number of lost MAC-d PDUs in the step C further comprises: TSN _x+i = mod(TSN _x +N _x +N _x+i-1 , 64), Where TSN _x+i is the serial number of the first MAC-d PDU in the data received by the subsequent x+i process; TSN _x is the serial number of the first MAC-d PDU in the data received by the previous x process; N _x is the number of MAC-d PDUs received by the previous x process; N _x+i-1 is the number of lost MAC-d PDUs. 6. A system for detecting the number of data loss, including a user equipment side and a base station side, characterized in that a transmission sequence number setting module is set on the user equipment side, and is used to set and represent MAC-es for the MAC-es protocol data unit PDU The TSN value of the first MAC-d PDU sequence number encapsulated in the PDU; Set on the base station side: The process difference calculation module is used to record the time of receiving data each time, and calculates the process difference of receiving data twice in a row according to the time; A data loss judgment module is used to judge whether the process is continuous according to the calculation result of the process difference calculation module, so as to determine whether there is data loss; The data loss number calculation module is used to receive the judgment result of the data loss judgment module, and when the process difference is 2, calculate the loss according to the TSN value of the data received twice before and after and the number of MAC-dPDUs in the sent data The number of MAC-d PDUs. 7. A base station, characterized by comprising: The process difference calculation module is used to record the time of receiving data each time, and calculates the process difference of receiving data twice in a row according to the time; A data loss judgment module is used to judge whether the process is continuous according to the calculation result of the process difference calculation module, so as to determine whether there is data loss; The data loss number calculation module is used to receive the judgment result of the data loss judgment module, and when the process difference is 2, calculate the loss according to the TSN value of the data received twice before and after and the number of MAC-dPDUs in the sent data The number of MAC-d PDUs.

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