A downlink synchronization method, system and mobile terminal for realizing cell initial search

Abstract

The invention provides a downlink synchronization method for realizing initial cell search, and relates to the technical field of communication. The method comprises the following steps: estimating the channel response to the received downlink pilot time slot data of the previous channel, performing denoising processing after obtaining the first channel estimation value, and combining it with the downlink pilot frequency after obtaining the second channel estimation value The downlink synchronization code of the time slot is slidingly correlated to obtain the reconstructed signal of the previous channel of the downlink pilot time slot; repeat the above steps for the continuously received downlink pilot time slot data of the latter channel to obtain the latter channel of the downlink pilot time slot Reconstructing the signal; synchronizing after combining the former reconstructed signal and the latter reconstructed signal. The invention also provides a downlink synchronization system and a mobile terminal for realizing initial cell search. The downlink synchronization method, system and mobile terminal for realizing the initial cell search of the present invention can improve the receiving sensitivity when the signal-to-noise ratio is low, and can effectively resist the interference of strong interference signals to received signals and cause misjudgment of related operations.

Description

technical field [0001] The present invention relates to the field of communication technology, and more specifically, relates to a downlink synchronization method, system and mobile terminal for realizing initial cell search. Background technique [0002] With the development of wireless communication technology, the number of mobile communication users is increasing rapidly, and the spectrum resources are limited. How to reduce interference and maximize the use of spectrum resources so that the limited bandwidth can carry as many users as possible is a problem for network manufacturers. key concerns. [0003] In the Time Division-Synchronous Code Division Multiple Access (TD-SCDMA, Time Division-Synchronous Code Division Multiple Access) mobile communication system, when the terminal equipment (UE, User Equipment) is turned on, the first step is to perform the initial cell search phase. The purpose is to select a suitable working frequency point and obtain downlink synchro...

AI Technical Summary

Problems solved by technology

[0010] However, the above two downlink synchronization methods all have deficiencies:

[0011] Although the computational complexity of the characteristic window method is low, the characteristics of the characteristic window of the signal power can only be reflected when the signal-to-noise ratio is greater than 0db. It affects the correct search and synchronization of the terminal; although the performance of the direct correlation method is better than that of the characteristic window method when the signal-to-noise ratio is low, when there is a strong uplink interference time slot signal, the anti-interference ability is poor, which may be due to the relatively high correlation peak value after the correlation operation. Large and lead to misjudgment, and high computational complexity

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