The Magnetic Target Detection Based On Orthonormalized Functions Decomposition

The technology of magnetic target detection based on orthonormalized functions decomposition is a new technology. This technology can be widely used in the military field and ocean engineering field, such as submarine detection, buried mine detection, sea bottom resources prospecting and so on.This paper analyses the principle of orthonormalized functions decomposition, compares the signal processing capability with digital filter, indicate orthonormalized functions decomposition constrains good magnetic anomaly signal in noisy detecting capability. Taking aim at effects of gaussian white noises on orthonormalized functions decomposition detection, the paper detailedly analyses the hoisting capacity of magnetic anomaly signal SNR, multi-channel orthonormalized functions decomposition detection algorithm is presented to estimate characteristic time and the distance between target and flight track, analyses the detecting-probability. But non-gaussian noises and colored noises are exiting in actual magnetic target detection. Taking aim at effects of non-gaussian noises on orthonormalized functions decomposition detection, the FIR low-pass filter was constructed to gaussianizate the non-gaussian noises, then orthonormalized functions decomposition was used and the effect on detection was simulated. Taking aim at effects of colored noises on orthonormalized functions decomposition detection, AR model and whitening filter was constructed to whitening the colored noises, then simulates the effect on the prewhitening orthonormalized functions decomposition. Then sets up the detection test system of orthonormalized functions decomposition, makes the actual subaerial detection test with a magnetic iron mass, respectively upgrades the SNR of magnetic anomaly signal mixed with gaussian white noises and magnetic interference to 3.75 d B and 11.35 d B. that validates the orthonormalized functions decomposition has a well effect on detection.Finally, the deficiencies in the research of this paper are summarized and the future research direction is provided.