A method for searching downlink synchronization code and user equipment

Abstract

The embodiment of the invention provides a method for searching for downlink synchronous codes and user equipment. The method is used for reducing the calculation amount for searching for the downlink synchronous codes and is high in searching accuracy. According to the method, a cell signal is received in advance. The method comprises the steps that a sample signal of the cell signal is determined; binarization processing is conducted on a value of each sampling point in the sample signal; each inflection point in the sample signal after binarization processing is conducted is determined; each inflection point comprises a sampling point jumped from 0 to 1 and a sampling point jumped from 1 to 0 in the binarized signal; according to the distance between the inflection points, the positions of the downlink synchronous codes are determined.

Description

technical field [0001] The invention relates to the field of mobile communication, in particular to a method for searching downlink synchronization codes and user equipment. Background technique [0002] In a mobile communication system, after the terminal is powered on, it needs to search for possible cells around it, select a suitable cell to log in, and then listen to paging on the network or initiate a call to establish a connection. The above process is called Initial Cell Search (InitialCellSearch). , ICS). Before the terminal logs in to the cell, it needs to complete the wireless interface synchronization process and establish synchronization with the cell. [0003] In Global System for Mobile communication (GSM) and Wideband Code Division Multiple Access (WCDMA) systems, there is a common synchronization code. When the user equipment (User Equipment, UE) detects this synchronization code, it can Synchronize with the cell. However, there is no similar common synchr...

AI Technical Summary

Problems solved by technology

[0009] The full-search and full-comparison method in the time domain and frequency domain is to do a correlation search in the global scope. Although the accuracy of establishing downlink synchronization at one time is high, the calculation amount is too large; the feature window search method and the search method based on the frame structure are aimed at Determine the position of SYNC_DL in advance or narrow its range, and then perform related calculations to correctly demodulate SYNC_DL. Although the computational complexity is reduced, the circuit complexity is increased, and a part of the success rate of demodulation is sacrificed.

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