Accidental access method for Time Division-Synchronous Code Division Multiple Access system

Abstract

The present invention discloses a random access method of time division synchronous code division multiple access system which is based on the distributed antennae; the method comprises the following processing that every antenna unit of the base station of the time division synchronous code division multiple access system implements the relevant operations on received random access signal and uplink synchronous code to obtain the corresponding result sequence; the relevant result sequence obtained by every antenna unit is processed to judge whether the user device which uses the uplink synchronous code for uplink access exists on every antenna unit; with the judging result, people decide whether to arrange a downlink forward-link physical access channel for the uplink synchronous code. With the technical proposal, at least two of the following beneficial effects are realized that the probability of system access conflict is reduced and the success rate of system access is increased.

Description

technical field [0001] The present invention relates to a wireless communication technology, and in particular, to a random access method of a Time Division-Synchronous Code Division Multiple Access system (TD-SCDMA, Time Division-Synchronous Code Division Multiple Access) based on a distributed antenna. Background technique [0002] The uplink synchronization process initiated by the user equipment in the TD-SCDMA system is as follows (see figure 1 ): 1. Each user terminal sends a specific uplink access signal containing an uplink random synchronization code (SYNC UL) on the uplink; 2. The base station obtains the uplink access signal of each user terminal by detecting each uplink synchronous random access signal. Timing information, the base station transmits timing adjustment information to each user terminal through a specific downlink channel (FPACH, forward physical access channel); 3. Each user adjusts its own timing according to the information sent by the base stati...

AI Technical Summary

Problems solved by technology

Take the application of distributed antenna-based TD-SCDMA base station in floor coverage as an example. Different unit antennas cover different floors. Although user equipment on different floors still belong to the same cell, each user equipment may pass through different channels on different floors. The antenna unit of the base station communicates with the base station equipment. If the user equipment on different floors selects the same pseudo-random sequence code to access the base station in the same frame, there are at least two problems in the base station using conventional access and conflict handling methods: ( 1) It is difficult for the base station to judge user access conflicts. The area covered by distributed antenna units generally does not have a large area range. Roughly the same, the signal characteristics of several user equipments on different floors detected by the base station accessing the base station with the same pseudo-random sequence code in the same frame are generally different from the signal characteristics of only one user accessing a certain antenna unit. (2) "User equipment on different floors select the same pseudo-random sequence code to access the base station in the same frame", although the uplink synchronization codes in this case conflict, but the downlink FPACH passes through different antenna units Therefore, there is actually no conflict. The base station uniformly executes the process of reselecting the uplink synchronization code and delaying retransmission for such users, which actually wastes the user's uplink access opportunities.

[0007] From the above content, it can be seen that the access effect of the existing TD-SCDMA base station based on distributed antenna is poor, the probability of system access conflict is relatively high, and the success rate of access is not high. Therefore, a solution is needed The technical scheme of above-mentioned problem

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