Method for detecting low signal-to-clutter ratio (SCR) moving target by stepped frequency coherent processing

Abstract

The invention relates to the field of detecting a moving target by a narrow-band ground-based radar in a clutter environment, and particularly relates to a method for detecting a low signal-to-clutterratio (SCR) moving target by a stepped frequency coherent processing. The method comprises the following steps: transmitting an inter-pulse same frequency signal by a radar with the frequency stepping between pulse group signals, firstly performing equal order AMTI on each carrier frequency pulse group signal in a group in the received signal processing; performing step frequency phase synthesisafter phase compensation on a time-aligned AMTI result of each carrier frequency; and finally completing coherent accumulation by a step frequency synthesized image at a slow beat; thereby completingseparation between the moving target and the remaining clutter, and achieving a purpose of improving the SCNR of the moving target detected.

Description

technical field [0001] The invention relates to the field of detection of moving targets by narrow-band ground-based radar in a clutter environment, in particular to a method for detecting low-signal-to-clutter ratio moving targets through step-frequency coherent processing. Background technique [0002] Detecting moving targets from strong clutter background is an important task of radar, and it is also a difficult point. When using traditional AMTI or point-optimized AMTD to deal with ground (sea) clutter in different environments, if the clutter environment is not estimated in real time and the filter coefficients are produced, clutter residues will inevitably be generated, making moving targets need In the detection process, it competes with these remaining clutters for energy. The clutter residue can be divided into two cases: one is that the filter null does not match the shape of the power spectrum of the clutter, resulting in a strong clutter residue in the sidelobe...

AI Technical Summary

Problems solved by technology

However, in the strong clutter environment and the low SNR of moving targets faced by radars, the SCNR of moving targets cannot be raised to a detectable level by simply relying on the stepping frequency, so it is necessary to rely on the combination of coherent accumulation methods to achieve the improvement. SCNR of moving target

[0004] The existing narrow-band radar technology schemes all realize the detection of moving targets under the assumption that the clutter filtering is complete or the SCR pre-filtering is at an acceptable level, but the actual echo signal processing results in the strong clutter area will contain some Intensity of clutter remains, so it will cause the signal processing model used to mismatch with the actual echo data, which means that the existing moving target detection methods sometimes fail when used in a strong clutter environment

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