Method for improving frequency domain anti-interference performance of direct-spread/frequency-hopping mixed spread frequency system

Abstract

The invention provides a method for improving the frequency domain anti-interference performance of a direct-spread / frequency-hopping mixed spread frequency system and aims to solve the problems of influence on the anti-interference performance caused by discontinuous phase and poor suppression performance of a fast time-varying interference signal. The method is implemented by adopting the technical scheme that: a distance measurement and speed measurement receiver having a frequency domain anti-interference function consists of a de-hopping module, a band-pass filter, a frequency domain anti-interference module, a demodulation module, a de-spreading module and a distance measurement and speed measurement module, which are sequentially connected on the same line in series, a frequency-hopping tracking module which is bridged on the de-hopping module and the frequency domain anti-interference module in parallel, and a carrier and code tracking module which is bridged on the demodulation module and the de-spreading module in parallel; and the frequency domain anti-interference module is divided into a windowing sub-module which is in frequency-hopping synchronization with the frequency-hopping tracking module, a fast Fourier transformation (FFT) sub-module, an interference suppression processing sub-module and an inverse FFT (IFFT) sub-module. The method is applicable to suppression of a narrow-band interference signal.

Description

technical field [0001] The invention relates to a digital baseband device mainly used in aerospace measurement and control and satellite navigation receiving systems, and is applicable to a method for suppressing narrow-band interference signals in a direct-spread frequency-hopping hybrid spread-spectrum system. Background technique [0002] There are two interference suppression problems in the prior art DS / FH hybrid spread spectrum system. The first is that the signal carrier phase of the DS / FH hybrid spread spectrum system is discontinuous, and the second problem is that the DS / FH hybrid spread spectrum system The performance of interference suppression for fast time-varying interference signals is not good. The reason for the first problem is that the carrier frequency of the direct-spread frequency-hopping hybrid spread-spectrum signal hops continuously according to the frequency-hopping pattern, which needs to occupy a wider radio frequency bandwidth, and the channel e...

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Problems solved by technology

[0004] The purpose of the present invention is to aim at the deficiencies in the application of the prior art in the direct spread frequency hopping hybrid spread spectrum system, to provide a synchronous windowing module assisted by a frequency hopping tracking module and a reasonable selection of the window function size, using the average value method Obtain the threshold, solve the effect of phase discontinuity on the anti-jamming performance, solve the poor performance of fast time-varying interference signal suppression, and improve the frequency-domain anti-jamming performance of the direct spread frequency hopping hybrid spread spectrum system

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