Method for reducing capturing time of spreading code in large dynamic range

Abstract

The invention provides a method for reducing capturing time of a spreading code in a large dynamic range and aims to provide a spreading code capturing method which is large in dynamic application range and can obviously shorten the capturing time. The technical scheme for realizing the method comprises the following steps of firstly, performing down-sampling and storage on baseband data subjected to down-conversion at two-time spreading code speed, reading stored data from a storage by a high-speed clock, dividing a frequency channel according to a Doppler frequency offset range, and performing Doppler frequency compensation on the read data according to the center frequency of each frequency channel; secondly, generating the corresponding spreading codes in the local place according to a code clock subjected to Doppler frequency compensation and corresponding to each frequency channel, and sampling and storing the spreading codes generated by different frequency channels by a two-time standard code clock; and finally, reading the spreading code corresponding to each frequency channel from the storage by the high-speed clock, and performing correlation calculation on the spreading codes and a signal subjected to the Doppler frequency compensation, wherein the pseudo-code phase and the Doppler which correspond to the highest correlation value are the final capturing result.

Description

technical field [0001] The invention relates to a method for acquiring a spread spectrum sequence of a direct sequence spread spectrum system. It is mainly used for the digital baseband equipment of the direct sequence spread spectrum system. The Doppler range reaches more than ±1MHz, and the Doppler change rate reaches more than 100KHz / S to quickly capture the spreading code of the direct sequence spread spectrum system under large dynamics. Background technique [0002] Spread spectrum communication is one of the most widely and deeply researched communication systems in the field of communication in the 21st century. Especially in today's increasingly complex channel environment and the social demand environment where personal communication attracts much attention, the excellent confidentiality and anti-noise performance of spread spectrum communication is very important. In the whole spread spectrum system, the capture of the spread spectrum code of the sender by the re...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a spread spectrum that adapts to a large dynamic range and can significantly shorten the capture time for the problems of long capture time and poor adaptability to rapid changes in Doppler in the large dynamic direct sequence spread spectrum system in the prior art code capture method

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