Two-stage threshold constant false alarm detection algorithm under strong ground clutter

Abstract

The invention discloses a two-stage threshold constant false alarm detection algorithm under strong ground clutters. Radar receiving echoes are subjected to down-conversion, decimation filtering, pulse compression and phase-coherent accumulation to form distance-Doppler two-dimensional data; and a two-stage threshold deletion average CFAR detection algorithm is adopted to determine the position ofthe target in the two-dimensional data, namely distance and Doppler information. Aiming at the problems of the ground reconnaissance radar CFAR detection technology, a two-stage threshold deletion average CFAR detection algorithm is designed, the discovery probability is improved, the false alarm probability is reduced, the calculation time is shortened, and the real-time requirement of a radar system is met.

Description

technical field [0001] The invention belongs to the field of ground reconnaissance radar digital signal processing, in particular to a two-level threshold constant false alarm detection algorithm under strong ground clutter. Background technique [0002] Radar automatic target detection is to allow the detector to change in real time according to the received echo signal, and automatically provide a detection threshold that changes with the clutter intensity, thereby avoiding interference such as clutter and noise, ensuring a constant false alarm probability and ensuring detection Probability, namely Constant False Alarm Rate (CFAR) detection problem. [0003] In the ground reconnaissance radar system, the target of interest is often located in the area where the ground clutter changes sharply, and the speed region of the slow target is roughly the same as that of the slow clutter, which increases the difficulty of target detection. Among the existing constant false alarm a...

AI Technical Summary

Problems solved by technology

Among the existing constant false alarm algorithms, the average CFAR cannot achieve ideal performance in a non-uniform environment, the false alarm probability of the ordered statistical CFAR is too high under strong ground clutter, and the computational complexity of the intelligent CFAR is too high, so it is not applicable For radar systems with high real-time requirements

[0004] The CFAR target detection method of ground reconnaissance radar mainly faces three problems. The first problem is that the superposition of strong ground clutter and the target leads to a decrease in the detection probability of the target; Using the same detection signal-to-noise ratio in all distance segments will increase the probability of false alarms; the third problem is that due to the large amount of data when reaching the target detection, in order not to affect the overall radar working sequence, the calculation time of the algorithm must be guaranteed as small as possible

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