Navigation interference suppression and signal amplification method for subspace projection

Abstract

The present invention discloses a navigation interference suppression and signal enhancement method for subspace projection, and mainly solves the problem that the existing method has poor and even failing anti-interference output and cannot obtain spatial gain. The method is implemented as follows: (1) estimating the covariance matrix for array receiving data, and performing eigen-decomposition;(2) estimating the number of interferences, and constructing an interference orthogonal complementary space with eigenvectors; (3) projecting the array receiving data to the interference orthogonal complementary space; (4) setting a satellite sequential number p to a cyclic variable; (5) performing frequency shift on data receiving anti-interference, correlating the data with the No.p local satellite signal, and recording the correlation peak and the main-to-side lobe ratio of the correlation peak; and (6) for a satellite with the main-to-side lobe ratio of the correlation peak larger than the threshold, using the correlation peak vector as beam forming to increase the strength of the satellite p. The method can suppress interference stably and enhance satellite signals remarkably, and spatial gain approximate to the theoretical value can be obtained for output signals. The method can be used for interference suppression and signal enhancement for a navigation satellite.

Description

technical field [0001] The invention belongs to the technical field of signal processing and relates to an array signal processing technology, which can be used for strong interference suppression and weak signal enhancement of a navigation receiver, and improves the output performance of the navigation receiver, and the effectiveness of the method is verified by measured data. Background technique [0002] The satellite navigation and positioning system can provide position, speed and time information all-weather and all-day, and has broad application requirements in the civil and national defense fields. However, due to the increasingly harsh electromagnetic environment and the very weak navigation signal reaching the receiver, the navigation receiver is extremely sensitive to interference. This characteristic of sensitivity to interference seriously affects the output performance of the navigation receiver. The output performance of the machine is very important. [0003...

AI Technical Summary

Problems solved by technology

However, due to the increasingly harsh electromagnetic environment and the very weak navigation signal reaching the receiver, the navigation receiver is extremely sensitive to interference. This characteristic of sensitivity to interference seriously affects the output performance of the navigation receiver. The output performance of the machine is very important

[0003] Traditional anti-interference algorithms such as SMI (Sample Matrix Inverse) method and LMS (Least Mean Square) iterative method have good anti-interference performance under ideal conditions, but in practice due to the existence of system Errors, such as inconsistent array patterns, multi-channel amplitude and phase errors, pointing errors, and small number of training samples, etc., lead to poor output performance or even failure of conventional anti-jamming methods

Another common anti-interference algorithm is the power inversion PI (Power Inverse) algorithm. The stronger the interference power, the better the suppression effect, so it can effectively suppress strong interference. However, this algorithm has no effect on navigation signals while suppressing interference. Enhanced, and possibly even weakened, no spatial gain of the signal

There is also an anti-jamming technology using an adaptive nulling antenna. This method can also adjust the array pointing to form a null at the interference place to achieve interference suppression, but there is also the problem that the signal space gain cannot be obtained.

[0004] The research on combining the above-mentioned anti-jamming algorithm through array optimization is also an aspect of anti-jamming technology. However, considering the complexity of the system in the actual system, the optimal array arrangement is generally limited when the number of array elements is limited, mainly through Traditional anti-jamming technology achieves interference suppression, but these jamming technologies often cannot obtain navigation signal space gain

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