Anti-narrowband interference method combining time domain and frequency domain

Abstract

The invention discloses an anti-narrowband interference method combining a time domain and a frequency domain. The method comprises the following steps: S1, performing digital down-conversion processing on an ADC input signal to obtain I and Q orthogonal baseband data; S2, performing windowing processing on the N-point baseband data; S3, performing FFT operation on windowed data to obtain FFT data; S4, performing power spectrum estimation operation on the FFT data, juging interference spectral lines and generating frequency domain weight to obtain 0 and 1 weights; S5, performing weighting processing on the FFT data obtained in the step S3 by using the weight obtained in the step S4; S6, performing IFFT operation on the weighted data to obtain time domain data; S7, inputting the time domaindata into a time domain anti-interference module to carry out time domain LMS adaptive filtering; and S8, selecting data and then outputting signals. According to the invention, by combining frequency domain processing and time domain processing, the advantages of frequency processing and time domain processing are fully combined, the defects of frequency processing and time domain processing areavoided at the same time, and the anti-interference processing and high-precision measurement capabilities are high.

Description

technical field [0001] The invention relates to the field of spread spectrum communication and satellite navigation signal processing, in particular to an anti-narrowband interference method combining time and frequency domains. Background technique [0002] At present, anti-interference processing has been widely used in satellite navigation, wireless communication, radar, sonar and other systems. One of its main purposes is to provide reliable interference suppression capabilities for receivers. The traditional anti-narrowband interference mainly consists of time-domain processing and frequency-domain processing, but both processing methods have their own shortcomings. Generally speaking, the time domain processing has fast convergence and good adaptability to non-stationary interference, but the correlation peak distortion caused by it is large, resulting in large ranging deviation. Frequency domain processing is accurate in spectrum suppression and small in ranging devi...

AI Technical Summary

Problems solved by technology

The traditional anti-narrowband interference mainly consists of time-domain processing and frequency-domain processing, but both processing methods have their own shortcomings

Generally speaking, the time domain processing has fast convergence and good adaptability to non-stationary interference, but the correlation peak distortion caused by it is large, resulting in large ranging deviation

Frequency domain processing has accurate spectrum suppression and small ranging deviation, but poor adaptability to non-stationary interference

A typical situation is that for pulse narrow-band interference in the order of Hz, the frequency domain processing is prone to a large number of bit errors and the loop loses lock, while the time domain processing can still work normally with fast convergence; at the moment of switching interference, the frequency domain method is easy Bit errors occur, but the time domain processing method does not have this problem

Another typical situation is that when the interference bandwidth exceeds 10% of the signal bandwidth, the time domain processing will cause a large ranging error, but the frequency domain processing method does not have this problem

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