CN1859034B - A method for dealing with uplink out-of-sync during soft handover - Google Patents

Abstract

The invention discloses a method for processing uplink out-of-sync during soft handover. After uplink out-of-sync occurs in some links during soft handover, RNC does not delete them (addition and deletion of links are completely triggered by other strategies, Such as: UE's intra-frequency measurement report, cell load control, etc.), but keep it in the active set, and notify the MDC entity to stop waiting and merging the uplink data of the link branch. Using the method for dealing with uplink out-of-sync during soft handover proposed by the present invention not only maintains the downlink soft-handover gain of the link, does not generate uplink soft-handover negative gain, but also avoids the loss caused by uplink out-of-sync Frequent addition and deletion of links can effectively solve problems caused by unbalanced uplinks and improve the quality of business services.

Description

A method for dealing with uplink out-of-sync during soft handover

technical field

The invention relates to a method for processing link out-of-sync in the WCDMA field, in particular to a method for processing up-link out-of-sync during soft handover.

Background technique

In the field of wireless communication, the air interface of the WCDMA system adopts the FDD (Frequency Division Duplex) system. A notable feature of it in mobility management is that it can use soft handover technology, that is, the UE (user terminal) can pass through multiple wireless links. The road communicates with the network. When multiple wireless links are merged in soft handover, the one with the better signal is selected through comparison, so as to achieve the purpose of optimizing the communication quality. Wherein, the uplink soft handover performs multipath combination in the RNC (Radio Network Controller), the uplink softer handover performs multipath combination in the NodeB, and the downlink soft handover performs multipath combination in the UE. Referring to Figure 1, the two active set (a set of all links currently connected to the UE) cells of the UE belong to two different NODEBs. During soft handover, when the downlink power of different links drifts, the DPB can be used to The (downlink power balance) function adjusts the downlink power to ensure that the signal power of each link when it reaches the UE is basically equal to achieve the best combination gain.

For the uplink, the UE can only transmit signals with a uniform power; when adjusting the uplink power, the UE combines the TPC (Transmit Power Control) commands of each link, and only when all links require a power increase The UE will increase the transmission power, and as long as there is a link that requires power reduction, the transmission power will be reduced. In this way, due to different cell coverage radii or different uplink interference in the cell, the signals arriving at NODEB from different links may be very different. For links that are relatively far away from the base station or have large uplink interference, the uplink signals are likely to fail to reach quality requirements, resulting in uplink out-of-step.

Based on the above analysis, in the soft handover state, if the uplinks are unbalanced, it will easily cause the uplink out-of-synchronization of some of the links, thus losing the uplink gain of the soft handover, or even generating negative gains. Because the MDC (macrodiversity control) entity in the RNC will cache and wait for the data of each branch to be merged and then transmitted to the upper entity, because one of the wireless links has an uplink out-of-sync, and the MDC does not know, so It affects the timely processing of uplink data and increases the uplink delay.

At present, if the uplink out-of-synchronization of the wireless link occurs during the soft handover, and the link is not synchronized within a certain period of time, the RNC will delete the link. Although this processing method can avoid the problem of negative uplink gain in soft handover caused by link out of synchronization, since the downlink pilot signal of the cell where the link is located at this time can meet the quality requirements of the UE active set, the UE will soon lose Reporting the co-frequency measurement report will cause the RNC to add it to the active set, and then there may be uplink out-of-synchronization, which will lead to frequent link additions and deletions, which not only increases unnecessary signaling load, but also may cause service failure. A drop in quality.

Contents of the invention

In view of the problems in the above-mentioned prior art, the purpose of the present invention is to provide a method for processing uplink out-of-sync during soft handover, which avoids frequent addition and deletion of links due to uplink out-of-sync, and solves the problem of Negative impact due to uplink imbalance.

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

A method for processing uplink out-of-sync during soft handover, mainly comprising the following steps:

A. After uplink out-of-sync occurs on some links during soft handover, the RNC does not delete the uplink out-of-sync message after receiving the uplink out-of-sync message (addition and deletion of links are completely triggered by other strategies, such as: UE's same-frequency measurement report , cell load control, etc.), but keep it in the active set, and notify the MDC entity to stop waiting and merging the uplink data of the link branch.

In the above process, step A includes:

A1. NODEB detects that one of the links is out of synchronization, sends a "wireless link failure indication" message to the RNC, and indicates that the cause of the failure is out of synchronization in the uplink;

A2. After receiving the link uplink out-of-sync message, the RNC notifies the MDC entity that the uplink out-of-sync is out, and the MDC does not wait for the uplink data of the link branch during merging processing.

Wherein, the method also includes the following steps:

B: After receiving the uplink synchronization message, the RNC notifies the MDC entity in time to resume waiting and merging processing of the uplink data on the link branch.

In the above process, step B includes:

B1, NODEB detects the uplink synchronization of the link, and sends a "radio link recovery" message to the RNC;

B2. After receiving the uplink synchronization message of the link, the RNC notifies the MDC entity that the uplink of the link has been synchronized, and the MDC resumes the merge processing of the uplink data of the branch of the link.

The method of the present invention for processing uplink out-of-sync during soft handover not only retains the existing downlink soft-handover gain, but also does not generate soft-handoff negative gain for uplink, and also avoids the uplink out-of-sync gain The phenomenon of frequently adding and deleting links effectively solves the negative impact caused by the unbalanced uplink; reduces the signaling load and improves service quality.

Description of drawings

Figure 1 is a schematic diagram of soft handover between different NODEBs

Figure 2 Flow chart of uplink wireless link out-of-sync processing during soft handover

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing:

With reference to Fig. 2, use the method of the present invention to deal with the uplink out-of-sync process of some links during soft handover as follows:

1. During a call or other business, soft handover occurs due to location movement of the UE. Assume that the current active set includes multiple links, which are respectively marked as RL1, RL2, ..., RLn, and these links The uplink signals of the link are combined at the RNC.

2. NODEB detects the uplink out-of-sync of RL1, sends a RADIO LINKFAILURE INDICATION message to RNC, and indicates that the reason for the failure is uplink out-of-sync.

3. The RNC does not delete the link after receiving the uplink out-of-sync message of RL1, but keeps it in the active set, and notifies the MDC entity that the uplink out-of-sync of RL1 is notified, and the MDC no longer waits for the uplink of the RL1 branch during the merge process data.

4. NODEB detects RL1 uplink synchronization, and sends a RADIO LINK RESTORE INDICATION message to RNC.

5. After receiving the RL1 uplink synchronization message, the RNC immediately notifies the MDC entity that the RL1 uplink has been synchronized, and the MDC resumes the merge processing of the RL1 branch uplink data.

Adopting the method for processing uplink out-of-synchronization during soft handover proposed by the present invention not only maintains the downlink soft handover gain of the link, does not generate uplink soft handoff negative gain, but also avoids the loss caused by uplink out-of-synchronization The phenomenon of frequently adding and deleting links can effectively solve the problems caused by the unbalanced uplink and improve the quality of business services.

Although the present invention has been illustrated and described with reference to the foregoing embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. .

Claims (4)

1. A method for processing uplink out-of-sync during soft handover, characterized in that: comprise the following steps: A. After the uplink out-of-synchronization of some links during soft handover, the RNC will keep the link in the active set after receiving the uplink out-of-synchronization message of the link, and notify the macro diversity control (MDC) entity to stop supporting the link The uplink data of the road is waited and merged. 2. The method for processing uplink out-of-sync during soft handover as claimed in claim 1, wherein step A comprises: A1. NODEB detects that one of the links is out of synchronization, sends a "wireless link failure indication" message to the RNC, and indicates that the cause of the failure is out of synchronization in the uplink; A2. After receiving the link uplink out-of-sync message, the RNC notifies the MDC entity that the uplink out-of-sync is out, and the MDC does not wait for the uplink data of the link branch during merging processing. 3. The method for processing uplink out-of-sync during soft handover as claimed in claim 1 or 2, is characterized in that, the method also comprises the following steps: B: After receiving the uplink synchronization message, the RNC notifies the MDC entity in time to resume waiting and merging processing of the uplink data on the link branch. 4. The method for processing uplink out-of-sync during soft handover as claimed in claim 3, wherein step B comprises: B1, NODEB detects the uplink synchronization of the link, and sends a "radio link recovery" message to the RNC; B2. After receiving the uplink synchronization message of the link, the RNC notifies the MDC entity that the uplink of the link has been synchronized, and the MDC resumes the merge processing of the uplink data of the branch of the link.

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