Space-time blind self-adapting anti-jamming method based on waveform characteristics

Abstract

The invention discloses a space-time blind self-adapting anti-jamming method based on waveform characteristics, which mainly solves the problem that the anti-jamming capability is lowered or even out of service in the presence of array manifold errors in the existing method. The method comprises the following steps that: data received by each matrix element realize the preliminary anti-jamming bythe space-domain sampling covariance matrix inversion method to synchronize a correlation peak so as to synchronize the data received by the matrix element with reference signals; the data received by the matrix element pass through a delay structure to output space-time array data, the space-time array data are used to estimate transformed space-time reference signals formed in a way that the space-time covariance matrix passes the synchronized reference signals through the delay structure, and the space-time reference signals and the space-time array data are used to estimate a cross-correlation vector rST; and the space-time data covariance matrix and the cross-correlation vector rST are used to calculate a space-time Wiener weight wST to carry out the space-time blind self-adapting anti-jamming. The invention has the advantage of strong anti-jamming capability, and can be used for the space-time anti-jamming under the condition that array manifold errors exist and satellite signals or the interfered arrival direction is unknown.

Description

technical field [0001] The invention belongs to the technical field of signal processing and relates to an anti-jamming method, which can be used to realize space-time anti-jamming processing of navigation receiving signals when there are array manifold errors and the prior information such as satellite signals or the direction of arrival of jamming is unknown. Background technique [0002] Satellite navigation and positioning systems can provide position, speed, and time information around the clock, and generally include satellite constellations, ground control / monitoring networks, and user receiving equipment. Satellite navigation has broad application requirements in the military and civilian fields. For example, it can provide electronic map navigation, automatic vehicle positioning and personnel search and rescue functions when it is used on land; it can provide flight-related surveillance, route guidance, missile positioning guidance, etc. when it is used in aviation. ...

AI Technical Summary

Problems solved by technology

Time-domain anti-jamming can filter out short-lasting pulse interference in the time domain, but since the navigation signal will be completely filtered out within the duration of the interference, this will increase the bit error rate during decoding; although frequency-domain anti-jamming can Effective against narrowband interference, but for broadband interference, its anti-jamming performance is inversely proportional to the bandwidth of the interference; airspace anti-jamming is based on the navigation array, using sidelobe cancellation, power inversion, linear constraint minimum variance adaptive beamforming and interference zero point preset and other technologies, when the degree of discrimination between interference and satellites in the airspace is large, it has good performance, but when the degree of discrimination between interference and satellites in the airspace is small, the anti-jamming effect in the airspace is poor or even invalid, and the number of anti-jamming is limited The number of array elements, in theory, can deal with N-1 interference at most, where N is the number of array elements; the space-frequency joint anti-interference means that the time domain sampling of each antenna is transformed into the frequency domain after Fourier transform, and the data of multiple adjacent frequency channels are combined for automatic Adaptive processing, space-frequency joint processing uses samples in the air domain and frequency domain to obtain signal information, which can deal with more interference than the single-dimensional domain, but space-frequency processing has a lot of calculations and is not easy to implement in engineering; space-time joint anti-jamming is At the same time, the antenna array and delay taps are used to obtain space-time samples, and an adaptive algorithm is used to achieve the purpose of suppressing interference. Since the space-time joint processing utilizes the information of the multi-dimensional domain, it can theoretically deal with NP-1 interference, where N is the array element. P is the number of delay taps, and for narrow-band interference with a small angle with the navigation signal space, the interference can be suppressed in the time domain and the anti-jamming performance can be improved

[0005] The above anti-interference methods usually have good anti-interference output performance under ideal conditions. In practice, there are inevitably array manifold errors, including array pointing errors, inconsistent array element patterns, mutual coupling between array elements, and channel amplitude and phase errors. Even with adaptive processing, the anti-jamming performance will be severely restricted

In addition, the above methods all need to know the prior information of the direction of arrival of the satellite signal or interference accurately in advance, but in practice, the acquisition of this prior information is often difficult to satisfy, and the inaccuracy of the prior information will lead to the loss of adaptive anti-jamming performance. severe decline

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