Joint optimal criterion based waveform design method of cognitive synthetic aperture radar (SAR)

Abstract

The invention provides a joint optimal criterion based waveform design method of a cognitive SAR. The method comprises the following steps that S1) a system parameter is initialized; S2) a joint optimal criterion objective function is established to maximize the echo SCNR and minimizing a time delay distinguishing constant; S3) a Lagrange multiplier method is used to convert the constraint optimization problem in the step S2) into a constraint-free optimization problem; S4) the constraint-free optimization problem in the step S3) is solved to obtain an expression of the optimal emission waveform based on the joint optimal criterion; and S5) according to an energy constraint condition, a Lagrange multiplier of the optimal emission waveform based on the joint optimal criterion in the step S4) is solved, and the optimal waveform is obtained. The emission waveform of the SAR is designed to use environment and target information, clutters are inhibited in the emission end, the SAR has a cognition capability, and the designed cognitive SAR has a higher distinguishing performance while inhibiting noises.

Description

technical field [0001] The invention belongs to the field of radar technology, in particular to a cognitive synthetic aperture radar waveform design method based on a joint optimal criterion. Background technique [0002] Synthetic Aperture Radar (SAR) has the characteristics of all-day, all-weather, and high-resolution, and can complete high-resolution imaging of the ground and target detection tasks. It uses the relative motion between the radar antenna and the target area to obtain high spatial resolution. Synthetic aperture radar has played an increasingly important role in the fields of terrain surveying and mapping, vegetation analysis, ocean and hydrological observation, environment and disaster monitoring, resource exploration, and detection of small changes in the earth's crust. [0003] When the conventional SAR works, it transmits the preset waveform and processes the received echo according to the preset mode, so as to complete the imaging detection of the obser...

AI Technical Summary

Problems solved by technology

Although these waveform design methods have improved the radar's cognitive ability and noise suppression ability, they have not considered the actual working requirements of SAR, and the designed waveforms generally have low resolution performance, which cannot be applied to high-resolution imaging and noise suppression in SAR. detection mission

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