A Motion Compensation Method for Synthetic Aperture Sonar Based on Multi-sensor Combination

Abstract

The present invention relates to the technical field of imaging sonar signal processing and synthetic aperture sonar motion compensation, in particular to a synthetic aperture sonar motion compensation method based on multi-sensor combination, which includes: obtaining sonar motion measured by inertial navigation based on a synthetic aperture sonar motion measurement system speed and the sonar motion speed measured by the Doppler log; the two are fused to obtain the optimal estimate of the sonar motion speed; the optimal estimate of the sonar motion speed is integrated to calculate the actual plane navigation of the sonar According to the actual plane track and the sky track of the sonar, the ideal plane track and the sky track under the least squares criterion are fitted; the actual plane track and the ideal plane track of the synthetic aperture sonar are calculated. Calculate the heave error between the actual sky track and the ideal sky track of the synthetic aperture sonar; calculate the actual sound path difference, and then convert it into time delay for the echo data collected by the synthetic aperture sonar compensate.

Description

technical field [0001] The invention belongs to the technical field of imaging sonar signal processing and synthetic aperture sonar motion compensation, and in particular relates to a synthetic aperture sonar motion compensation method based on multi-sensor combination. Background technique [0002] Synthetic aperture sonar uses the movement of the small-aperture matrix along the azimuth direction (track direction) to synthesize a virtual large aperture, and performs coherent superposition processing on the received echoes at different positions according to the spatial position and phase relationship to obtain high-resolution images. The prerequisite for synthetic aperture sonar to achieve high-quality imaging is that the sonar moves in a straight line at a constant speed along the azimuth direction. In actual work, affected by factors such as water flow, wind and waves, the synthetic aperture sonar will deviate from the ideal motion state and produce motion errors. The far...

AI Technical Summary

Problems solved by technology

However, the premise of Kalman filtering to achieve optimal estimation is that the model is accurate and the statistical characteristics of random interference signals are known, which is often difficult to achieve in real systems; and for Kalman filtering, model differences can easily lead to estimation accuracy degradation and filtering divergence The phenomenon that causes the problem that the sonar movement speed cannot be accurately calculated

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