Anti-narrowband interference implementation method of satellite receiver based on fpga

Abstract

The invention discloses a satellite receiver narrowband interference prevention realization method based on FPGA and mainly aims to solve a problem of inaccurate estimation on the interference frequency point position existing in the prior art. According to the method, the FPGA and a soft core MicroBlaze are employed, the intermediate frequency sampling data of a satellite receiver is firstly received through the FPGA; a Gauss-Newton self-adaptive algorithm is secondly utilized in the soft core MicroBlaze to accomplish estimation on an interference frequency point position parameter vector; thirdly, a module method is employed to design a filtering coefficient vector according to the interference frequency point position parameter vector; lastly, the filtering coefficient vector is taken by a time domain finite impulse response filter FIR as a filtering coefficient, and narrowband interference signals of a satellite receiver are inhibited. The method is advantaged in that a dual-time-domain parallel processing mechanism is employed, compared with the prior art, signal processing timeliness is not only improved, but also stability of estimation on the interference frequency point position parameter vector is improved, and the method can be applied to satellite navigation systems.

Description

technical field [0001] The invention belongs to the technical field of data processing, and in particular relates to a method for realizing anti-narrowband interference, which can be used in a satellite navigation system. Background technique [0002] Due to the constraints of some inherent factors of the satellite navigation system itself, some weaknesses that are difficult to restrain are caused. For example, the strength of the satellite navigation signal arriving at the ground receiver is very weak, and it is easily subject to various intentional or unintentional interferences, which will cause the satellite receiver to fail to capture the navigation signal or cause the receiver to lose lock; the interference signal for the satellite receiver can generally be divided It is narrowband interference signal and broadband interference signal. The narrowband interference signal considered in engineering is defined as the interference signal bandwidth is within 10% of the usefu...

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Problems solved by technology

[0004] The time-domain adaptive suppression method, such as the least mean square algorithm LMS, is mainly based on the gradient descent algorithm, and each iteration needs to estimate the gradient value; due to the random noise in the signal, the gradient value estimation is not accurate, which will lead to interference Narrowband interference whose signal bandwidth is 5% to 10% of the useful signal bandwidth cannot be completely suppressed

[0005] The transform domain suppression method mainly estimates the interference position by performing fast Fourier transform on the received data. In the case of high sampling rate and small samples, the frequency resolution is very low, and the position of the interference frequency point cannot be accurately estimated.

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