Method for overcoming soft handoff dropped call in third generation mobile communication system

Abstract

The invention advances a method for overcoming call disconnection in soft swithicng in third-generation mobile communication system, in macro diversity state, when one or plural ones of the user equipment received downlinks are outside the transmitting window, network controller removes these links; if these links qualities are certainly good, the user equipement will report their qualities by in-frequency measurement, and the network controller adds them to an activation set again, and after this, the user equipment received downlink links are bound to be inside the transmitting time window. And the method assures user equipment able to normally switch, and remarkably raises user equipment soft-switching success rate and the whole operating performance of WCDMA system.

Description

technical field [0001] The present invention relates to a soft handover control method in the WCDMA (Wideband Code Division Multiple Access) R99 system, and in particular to the transmission and reception time difference (Rx-Tx time difference) of the internal mobile terminal of the user equipment UE (User Equipment) in the WCDMA system Internal measurement report results, methods to overcome soft handover dropped calls. Background technique [0002] With the emergence of the third-generation mobile communication system, the advantages of soft handover technology as a WCDMA system have gradually been applied, that is, when a mobile station establishes contact with a new cell during its movement, it does not immediately interrupt the connection with the original cell, Implementing soft switching within the frequency can greatly reduce the call drop rate. During the soft handover process, the mobile user can combine the downlink signals from different cells for signal process...

AI Technical Summary

Problems solved by technology

With the movement of the UE or the clock drift between NODE Bs, the receiving time of the downlink changes, and it is likely to fall outside the time window before the sending time of the UE, and the UE cannot correctly demodulate one or more downlinks, so that The quality of the UE downlink deteriorates, which may eventually lead to call drop

[0005] Compared with other systems (such as GSM system and CDMA system), WCDMA system has many special features of its own. Since its development time in various countries is relatively short, there is not much information on the specific realization of this problem. Check, in the patents that have been published, there is no patent on how to solve the problem of soft handover failure caused by time drift in the case of cross-NODE B macro diversity, which can be referred to and compared

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