Method and apparatus for capturing spread spectrum communication code

Abstract

The invention provides a method and apparatus for capturing a spread spectrum communication code. The method comprises: carrying out N-times matching filtering on a receiving signal after frequency folding and a local spreading code, carrying out controlling of segmented matching filtering on the receiving signal after frequency folding and the local spreading code for each matching filtering to obtain a segmented matching filtering result of each matching filtering; according to the segmented matching filtering result of each matching filtering, acquiring a matching filtering result after each matching filtering; and carrying out non-coherent accumulation on the matching filtering results after the N-times matching filtering and determining capturing information of a spread spectrum communication code based on the non-coherent accumulation result. With the method provided by the invention, the frequency searching units are reduced by using frequency folding, so that the capturing speed is increased; and the information sequence symbol overturning is eliminated by using the segmented matching filtering method, so that the time cost of capturing the spread spectrum communication code is lowered and the capturing probability is improved.

Description

technical field [0001] The invention relates to the technical field of communication, in particular to a method and device for acquiring a spread spectrum communication code. Background technique [0002] Spread spectrum communication has the advantages of strong anti-interference ability and convenient code division multiple access, and is widely used in security communication, GPS navigation and other fields. How to quickly capture spread spectrum communication codes is a very critical issue in spread spectrum communication. [0003] In the process of capturing spread spectrum communication codes, there are many factors that will affect the final result and lead to performance degradation. Among them, the Doppler frequency deviation caused by large dynamics and the information sequence symbol flip caused by long code period spreading are the most critical Two big reasons. When there is a Doppler frequency offset, capturing the spreading code becomes a two-dimensional sea...

AI Technical Summary

Problems solved by technology

Among them, the sliding correlation method is less complex to implement, but the capture time is longer

The matched filtering method can be regarded as a parallel sliding correlation method. Compared with the traditional sliding correlation method, it improves the degree of parallelism, thereby greatly reducing the capture time, but at the same time increases the consumption of resources.

However, when the information symbols flip violently within a spreading sequence period, the above two algorithms will fail

The PMF-FFT algorithm can solve the problem of violent flipping of information sequence symbols, but because its two-dimensional search volume is still large, its capture speed is too slow and the improvement space is limited

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