WCDMA subdistrict searching time slot synchronization method and system

Abstract

The present invention provides a method and a system for synchronously searching time slot in the cells of the WCDMA system; the method comprises the following steps that the parameters are initialized; the input digitalized I-route and Q-route data are implemented with frequency deviation compensation; the relevant values of the I and Q data of the 256 chips with the main synchronous code, which are corresponding to every time slot from an assumed time slot boundary, are calculated; the relevant values are implemented with power calculation and the integer of the calculation result represents the power value which is converted into floating point number to indicate the power value; the floating point number represents the power value and the value is added with the anterior time slot accumulated value read from the memory; the steps are repeated until M time slots are added; N largest peak values and the corresponding chronological positions are found; the process of interruption is applied to the DSP to wait for the next treatment. The method and the system can accurately position the time slot boundary of small cell and confirm difference small cells of different diameters or scrambling codes in the same small cell, which is beneficial to searching cell.

Description

technical field [0001] The present invention relates to a method and system for synchronizing time slots in a Wide-band Code Division Multiple Access (WCDMA) system in the communication field, and in particular to a method and system for synchronizing time slots in a WCDMA cell search . Background technique [0002] The cell search process or synchronization process in the asynchronous WCDMA system is very different from the synchronous system. Since each cell in the asynchronous UTRA WCDMA system uses different torsion codes and not only different phase offsets, the current terminal Technically speaking, it is not possible to complete the search for 512 codewords within 10ms without any prior information; if you want to complete the search for 512 codewords, you will need to perform multiple cell search comparisons , so that the user needs to wait for a long time from power-on to accessing the network. [0003] Therefore, using the synchronization channel for cell search ...

AI Technical Summary

Problems solved by technology

The acquisition probability of this method is not high, because in practical applications, due to the harsh environment of mobile communication, the received signal is very complicated, and various fading is also relatively serious. If the received value is simply judged by the threshold, it may cause acquisition failure or require an iterative process of setting the threshold multiple times

In addition, since all base stations are sending the same basic synchronous channel, the mobile station may receive signals from several base stations; due to the influence of multipath, it will also cause the receiving matched filter to output multiple peaks

The current method does not process multiple peaks exceeding the threshold value, which cannot meet the processing requirements of WCDMA terminal cell search for multi-cell situations, and needs to configure multiple parameters such as threshold value, accumulation times, and peak occurrence times. Difficult to judge

Images