A method of target detection under low signal-to-noise ratio based on probability and statistics

Abstract

The invention belongs to the technical field of radar signal processing, and particularly relates to a target detection method under the condition of a low signal-to-noise ratio based on probability statistics. According to the invention, the single pulse within the observation time is taken as a processing object, an interested observation region is covered by adopting a simultaneous multi-beam method, a target echo envelope is obtained through performing pulse compression on all pulse echoes within the observation region, then echo envelope detection frequencies of different azimuth units and distance units are counted and recorded after performing constant false alarm detection on the echo envelope, and finally a probability histogram is drawn, and detection and judgment are performed according to the threshold-exceeding frequency distribution of the different azimuth units and distance units so as to complete the target detection process. The method provided by the invention is notonly suitable for single-pulse target detection under the low signal-to-noise ratio, but also can serve as an auxiliary detection means for non-ideal target detection after long-time accumulation ofmultiple pulses. The method provided by the invention is small in data processing amount, meets real-time processing requirements of a hardware platform and is suitable for engineering implementation.

Description

technical field [0001] The invention belongs to the technical field of radar signal processing, in particular to a target detection method under the condition of low signal-to-noise ratio based on probability statistics. Background technique [0002] Target detection with low signal-to-noise ratio is a hot topic in modern radar research. As the main electronic information equipment in modern warfare, radar has always been responsible for the tasks of battlefield information acquisition, processing and circuit realization. Only by determining whether the target of interest exists and obtaining relevant information such as target speed and angle can the target be positioned, tracked, and imaged. identify. As the electromagnetic environment in the battlefield becomes more and more complex, clutter and noise interference are serious, the use of stealth technology reduces the detectable characteristics of the target, and the low interception technology uses extremely wideband fr...

AI Technical Summary

Problems solved by technology

However, if the detection threshold is set as a constant, then under non-stationary clutter, when the average power of the background clutter increases by several decibels, the probability of false alarms will rise sharply, so that the computer processing capacity will be saturated, affecting the normal operation of the radar system

Therefore, the constant false alarm rate detection method is adopted in the process of radar target detection, and the detection threshold is adaptively changed according to the change of clutter intensity to obtain the maximum detection probability and constant false alarm probability. The signal-to-noise ratio is required, and the detection result is not good under the condition of low signal-to-noise ratio

Many scholars have proposed long-term accumulation methods for target detection under low SNR conditions. However, with the development of new system radars and increasingly complex electromagnetic interference environments, long-term accumulation target detection methods may not necessarily effectively improve signal-to-noise ratios. Noise ratio, so the target detection effect is not ideal

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