A Radar High Resolution Imaging Method Based on Multi-beam Scanning

Abstract

The invention discloses a radar high-resolution imaging method based on multi-beam scanning, which is applied in the field of radar imaging, uses digital beam forming technology to form multiple receiving sub-beams, and adopts the "folding fan" working mode when the receiving beam sweeps the forward-looking area , reduce the forward-looking Doppler ambiguity area; at the same time, through the echo superposition of multiple beams, a larger Doppler bandwidth is obtained, and the target azimuth resolution in the large forward-squinting area of ​​the airborne platform is improved, and a large-scale radar large-squinting area is realized. High-resolution imaging: The method proposed in this application can be used to solve the inherent contradiction between the resolution and the blind area of ​​forward-looking imaging existing in the existing Doppler beam sharpening technology.

Description

technical field [0001] The invention belongs to the field of radar detection and imaging, and in particular relates to a scanning radar forward-looking azimuth high-resolution technology. Background technique [0002] Radar uses emission and electromagnetic waves to realize functions such as target reconnaissance, surveillance, positioning, and identification. Its operating spectrum is wide. Compared with optical detection, it can work all day and all day under the influence of various adverse weather and environmental factors. . Its wide adaptability has very wide application and research value in military and civilian fields such as marine and hydrological observation, environmental and disaster monitoring, land and sea tracking and rescue. [0003] In radar imaging, the realization of radar front squint imaging is of great significance for target reconnaissance, surveillance, positioning, tracking, target recognition of friend and foe, and precise guidance. Due to the D...

AI Technical Summary

Problems solved by technology

Due to the Doppler symmetry and the small Doppler gradient in the forward-looking area of ​​the carrier aircraft, it is difficult to achieve high azimuth resolution of adjacent targets

In the document "Zheng S.X.LIZ.BAO.Highly Squint DBSImaging[J].Modern Radar,2004,1:008.", a Doppler beam sharpening imaging method under a large oblique angle of view is proposed, using narrow beam scanning , to achieve large-scale Doppler beam sharpening imaging in the airborne oblique forward-looking area. Although this method can improve the target azimuth resolution to a certain extent, the echo accumulation time of the narrow beam sweeping across the target point is short, and it is difficult to achieve azimuth phase resolution. For the resolution of adjacent targets, especially in the large front squint area, the rate of change of the target Doppler gradient is small, and it is more difficult to achieve the azimuth resolution of adjacent targets

In the document "Bao H R W T, Bao-chang Z L.A Novel Algorithm for StitchingDoppler Beam Sharpening Images Based on INS Information [J]. Journal of Electronics & Information Technology, 2012, 6:012.", a Doppler algorithm based on inertial navigation information is proposed. The essence of the Le beam sharpening image stitching algorithm is to use the azimuth fast Fourier transform to increase the coherent accumulation time of the echo and improve the azimuth resolution of the Doppler beam sharpening, but the use of a wide beam will cause the beam to sweep the front view In the region, due to the Doppler symmetry problem, the imaging results are aliased, which affects the imaging performance

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