CN1968524A - Method for shortening high-speed downlink packet access service time-delay in affirmance mode - Google Patents

Abstract

The invention relates to a method for shortening the high-speed descending group access service time delay of confirmation mode, wherein when the access service is switched from source node B to the target node B, the wireless chain control layer transmits the non-treated protocol data of source node B to the target node B. the invention can reduce processes that RLC sends POLL (or UE detects its lost PDU), and UE sends state report, to reduce the service time delay at AM mode and HSDPA spans node B.

Description

A kind of method that shortens the high speed downlink grouping access business time delay under the affirmation mode

Technical field

The present invention relates to the processing method of high speed downlink grouping access business under the Radio Link control technology, particularly affirmation mode in the broadband CDMA system.

Background technology

RLC (Radio Link Control, Radio Link control) at WCDMA (Wide Code DivisionMulti Access, Wideband Code Division Multiple Access (WCDMA)) major function in is transfer of data, flow control, encryption and decryption processing etc., the mode of operation of its support has TM (Transparent Mode, transparent mode), UM (Unacknowledged Mode, Unacknowledged Mode) and AM (Acknowledged Mode, affirmation mode), for the transfer of data of AM, guarantee the reliable transmission of data by sliding window and retransmission mechanism.

The re-transmission of RLC is a kind of mechanism in order to guarantee reliability of data transmission, correctness and to define in the AM pattern.

RLC is with PDU (Proctol Data Unit, protocol Data Unit) this PDU can be placed in the retransmission queue after the transmission, the re-transmission content of RLC depends on the status report that data receiver is sent, status report is made up of one or more status PDU, status PDU is indicated SN (the Sequence Number of the PDU that retransmit to data sending terminal, sequence number) scope, after data receiver is received status report, can determine which PDU in the retransmission queue can be deleted according to the information in the status report, which PDU needs retransmits, and the transmission priority that retransmits PDU will be higher than the priority level of the PDU that sends for the first time.

HSDPA (High Speed Downlink Packet Access, high speed downlink packet inserts) be by adopting shorter TTI (Transmission Time Interval, Transmission Time Interval) (2ms), the back 3G technology that can bring the high-speed downstream business experience of HARQ (Hybrid Automatic Repeat reQuest mixes automatic repeat requests) and high order modulation (16QAM etc.) to the user.

The switching of HSDPA mainly contains three types:

Concentrate the Serving cell that changes HS-PDSCH (High Speed Physical Downlink Shared Channel, high-speed physical downlink shared channel (HS-PDSCH));

Change the Serving cell of HS-PDSCH channel when carrying out direct-cut operation at DPCH (Dedicated Physical Channel, DPCH);

When carrying out soft handover, the DPCH channel changes the Serving cell of HS-PDSCH channel.

After UE made a call, RRC (Radio Resource Control, Radio Resource control) layer can be mapped to business different transmission channels according to customer service type and mapping policy.Because this moment, the UE business was HSDPA, naturally be mapped to HS-DSCH (High Speed Downlink SharedChannel, high speed descending sharing channel) on, simultaneously, if condition is suitable, for eating dishes without rice or wine to obtain higher throughput, according to the handoff algorithms of HSDPA, after arriving certain thresholding and time point, the Serving cell of HS-DSCH can be updated on the better sub-district of signal quality.

But cell-of-origin and Target cell in the service cell updating process of HS-DSCH do not belong to same Node B, and when this moment, high level adopted the AM mode of operation, Macd-hs among the former Node B can reset, be trapped in this Macd-hs (protocol entity this moment, MAC entity a kind of, in Node B, realize) in and the data that do not send to UE as yet will all lose, after a period of time, which PDU UE can indicate to the RNC status report is not received and requires transmitting terminal with data re-transmission, and RNC also can resend the data of losing.

Above-mentioned processing mode sends though also can guarantee the normal, reliable of data, owing to comprised following flow process:

RLC sends out POLL (or perhaps UE oneself detected lose PDU);

UE status report (STATUS REPORT);

RLC retransmits corresponding data; And

UE correctly receives.

Above-mentioned processing procedure must be brought service delay, this is for being a defective to the high HSDPA business of rate requirement, user's High Data Rate is experienced and may be a greater impact, so this just makes that how to reduce service delay when this scene takes place has practical significance as far as possible.

Summary of the invention

The object of the present invention is to provide a kind of method that shortens the HSDPA service delay under the affirmation mode, when guaranteeing that the data normal reliable sends, reduce to guarantee that user's High Data Rate is experienced owing to stride the service delay that Node B data loss while switching brings.

To achieve these goals, the invention provides a kind of method that shortens the high speed downlink grouping access business time delay under the affirmation mode, after described high speed downlink grouping access business switched to target Node B from source Node B, wireless chain control layer initiatively retransmitted to described target Node B with the protocol Data Unit that described source Node B has been untreated.

Above-mentioned method, wherein, the protocol Data Unit that described source Node B has been untreated comprises and sends to subscriber equipment by described source Node B, but do not receive that subscriber equipment returns the protocol Data Unit of acknowledge message, sent to described source Node B, but described source Node B does not also send to the protocol Data Unit of subscriber equipment.

Above-mentioned method wherein, specifically comprises the steps:

Steps A, radio resource control layer judge that described high speed downlink grouping access business switches to described target Node B from described Node B, notifies described wireless chain control layer to carry out the protocol Data Unit retransmission process;

The sequence number of the protocol Data Unit that step B, described wireless chain control layer have been untreated according to the described source of the Notification Validation of described radio resource control layer Node B;

Step C, described wireless chain control layer initiatively retransmits to described target Node B with the sequence number corresponding protocols data cell that described step B determines.

Above-mentioned method, wherein, among the described step B, the scope of the sequence number of the protocol Data Unit that described source Node B has been untreated is [vt (A), vt (S-1)], wherein vt (S) is the sequence number of the protocol Data Unit that sends for the first time of next expectation, the SN of the protocol Data Unit that vt (A) is identified for next expectation.

Above-mentioned method, wherein, described step C specifically comprises:

Step C1, described wireless chain control layer determine the sequence number corresponding protocols data cell that described step B determines;

Step C2, described wireless chain control layer is placed into retransmission queue in order with the protocol Data Unit of determining among the step C1 and sends.

The method of the HSDPA service delay under the shortening affirmation mode of the present invention retransmits to UE by the PDU that has been untreated by the preceding source Node B of RLC active will the switching, reduced the flow process that RLC sends out POLL (or perhaps UE oneself detect lose PDU) and UE status report (STATUS REPORT), therefore reduced the service delay when HSDPA strides Node B switching under the AM pattern, guaranteed also simultaneously that the data normal reliable sends, realized simple.

Description of drawings

Fig. 1 is the schematic flow sheet of method of the present invention.

Embodiment

From the description of background technology as can be seen, in a period of time after taking place was switched in the sub-district of striding Node B, the rlc layer of network side can be waited for the status report of LIE, waited to receive behind the status report to retransmit because of the Macd-hs data of losing that reset again.

A kind of method that shortens the HSDPA service delay under the affirmation mode of the present invention will be switched the PDU that preceding source Node B has been untreated by rlc layer and initiatively retransmit to UE in that the back switch to take place, and shorten effectively that HSDPA is professional to be prolonged in fact.

The above-mentioned PDU that has been untreated comprises following two types PDU:

PDU has sent to source Node B, and also oneself sends to UE with PDU to source Node B, but UE does not also return acknowledge message; With

Oneself sends to source Node B PDU, but source Node B does not also send to UE with PDU before switching.

Be convenient description, the Node B under before the Serving cell switching of HS-DSCH is called source Node B, be called target Node B and Serving cell is switched affiliated afterwards Node B, the two is different Node B.

At transmitting terminal, under the AM mode of operation, agreement has been stipulated following state variable:

Vt (S), the SN of the PDU that next expectation sends for the first time, it upgrades after sending a PDU who sends for the first time;

Vt (A), the SN of the PDU that next expectation is identified, it constitutes the lower edge of send window;

Vt (MS), the SN of the maximum of the PDU of the transmission that is allowed to, it constitutes the upper edge of send window, and the size of send window is vt (MS)-vt (A)+1, and as Vt (S) during more than or equal to vt (MS), RLC will can not send new PDU to UE simultaneously.

If vt (A)＜vt (S) show that then all oneself obtains confirming vt (A) all PDU before, but this fashion has the data that send but be not identified, the SN of this part PDU

[vt (A), vt (S)];

If vt (A) 〉=vt (S) illustrates that so the data of all transmissions all are firmly established.

A kind of method that shortens the HSDPA service delay under the affirmation mode of the present invention comprises the steps: as shown in Figure 1

Step 1, rrc layer are judged the HSDPA business and are switched to the switching of striding Node B, then notify rlc layer to carry out the PDU retransmission process;

Step 2, rlc layer are determined the SN of the PDU that the preceding source Node B of switching has been untreated after the instruction of carrying out the PDU re-transmission that receives rrc layer;

Step 3, rlc layer initiatively retransmits to target Node B according to the SN that retransmits the PDU that determines in the PDU determining step with the PDU of correspondence, at this, the PDU of the sequence number correspondence determined in the step 2 is put into retransmission queue retransmit and get final product.

Below the present invention is further described in detail.

The SN of the PDU that has been untreated for source Node B determines, supposes current vt (S)=x, describes for convenient, is referred to as old PDU at this PDU with SN＜x, and the PDU of SN 〉=x is referred to as new PDU, and old PDU is meant the PDU that has sent to source Node B before the switching; New PDU is meant the PDU that is about to send to after the switching among the target Node B.

Therefore, in the method for the HSDPA service delay under the shortening affirmation mode of the present invention, the SN that switches the PDU that preceding source Node B has been untreated certainly at vt (A) between the vt (S-1).

In the step 3 SN directly being placed into retransmission queue at vt (A) in order successively to the PDU between the vt (S-1) sends and gets final product.

The above only is a preferred implementation of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (5)

1. method that shortens the high speed downlink grouping access business time delay under the affirmation mode, it is characterized in that, after described high speed downlink grouping access business switched to target Node B from source Node B, wireless chain control layer initiatively retransmitted to described target Node B with the protocol Data Unit that described source Node B has been untreated.

2. method according to claim 1, it is characterized in that, the protocol Data Unit that described source Node B has been untreated comprises and sends to subscriber equipment by described source Node B, but do not receive that subscriber equipment returns the protocol Data Unit of acknowledge message, sent to described source Node B, but described source NodeB does not also send to the protocol Data Unit of subscriber equipment.

3. method according to claim 1 and 2 is characterized in that, specifically comprises the steps:

Steps A, radio resource control layer judge that described high speed downlink grouping access business switches to described target Node B from described Node B, notifies described wireless chain control layer to carry out the protocol Data Unit retransmission process;

The sequence number of the protocol Data Unit that step B, described wireless chain control layer have been untreated according to the described source of the Notification Validation of described radio resource control layer Node B;

Step C, described wireless chain control layer initiatively retransmits to described target Node B with the sequence number corresponding protocols data cell that described step B determines.

4. method according to claim 3, it is characterized in that, among the described step B, the scope of the sequence number of the protocol Data Unit that described source Node B has been untreated is [vt (A), vt (S-1)], wherein vt (S) is the sequence number of the protocol Data Unit that sends for the first time of next expectation, the sequence number of the protocol Data Unit that vt (A) is identified for next expectation.

5. method according to claim 3 is characterized in that, described step C specifically comprises:

Step C1, described wireless chain control layer determine the sequence number corresponding protocols data cell that described step B determines;

Step C2, described wireless chain control layer is placed into retransmission queue in order with the protocol Data Unit of determining among the step C1 and sends.