Sea clutter suppression and target detection method based on singular spectrum analysis

Abstract

The invention relates to a sea clutter suppression and target detection method based on singular spectrum analysis (SSA). The method comprises the following steps of firstly, calculating an autocorrelation function of echo data, constructing a Toeplitz matrix of echo data by taking a first zero crossing point position of the autocorrelation function as a dimension for reconstructing a track matrixof the radar echo data, solving a quantity of PCA (Principal Component Analysis), and judging whether echo comprises a target according to the quantity of the PCA; performing singular spectrum analysis on the radar echo, reconstructing time sequences corresponding to a principle component and a minor component (MCA), and when the echo contains the target, taking the time sequence corresponding tothe maximum principle component, and discarding the time sequences corresponding to other components; otherwise, selecting the time sequence corresponding to the minimum minor component, and abandoning the time sequences corresponding to other components. A processing process can be regarded as self-adaptive filtering independent of an echo statistical model, sea clutter intensity in the processed radar echo data is effectively suppressed, and a detection probability of subsequent weak and small targets is improved.

Description

technical field [0001] The invention belongs to the technical field of target detection, relates to target detection under the background of sea clutter, and is a sea clutter suppression and target detection method based on singular spectrum decomposition. Background technique [0002] Sea clutter refers to the echo generated when the radar beam for sea observation hits the sea surface. The characteristics of sea clutter are closely related to the area covered by the radar beam, the height of the waves (that is, the sea state), the main frequency and bandwidth of the radar, and other factors. , usually the sea clutter reflects the movement characteristics of the waves caused by gravity and the fretting characteristics of the tubular breaking waves caused by the sea surface tension. The change presents non-stationary and non-linear characteristics, as shown in the attached figure 1 Shown in (a) and (b) are the time-domain magnitude diagrams of the sea clutter data (http: / / so...

AI Technical Summary

Problems solved by technology

One of the classic solutions is to dynamically track the statistical characteristics of radar echoes, and process them in segments according to the principle of similar characteristics, which solves some problems at the engineering level. However, with the improvement of sea conditions, radar echoes The segmentation of data is getting shorter and shorter, and finally there is no essential difference with the situation of short-term observation, resulting in a high false alarm probability and a low detection probability when detecting weak and small targets. Therefore, the signal based on statistical characteristics The processing method can no longer meet the needs of engineering under high sea conditions, and it is necessary to find a sea clutter suppression method that does not rely on statistical models to solve this problem

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