基于恒虚警率的门限判决系数寻优研究

在雷达信号检测系统中,对于一定的检测门限,如果噪声或杂波电平增大一点,虚警率便会大大增加,同时使发现概率降低,这样便降低了雷达系统发现目标的能力,因此在现代雷达信号检测系统中,为了保证一定的发现概率,一般采取恒虚警率(CFAR)处理,在雷达系统进行恒虚警处理时,由于杂波强度可能偏离统计平均值而产生起伏,此时采用理论的门限判决系数将使虚警率大大增加。通过对雷达信号检测恒虚警性能的研究,分析了有限参考单元数对虚警率及发现概率的影响,同时提出一种有效的寻优算法在恒虚警检测中对实际的门限判决系数进行实时的动态寻优,使检测系统始终保持在恒虚警的工作状态中。

Study of Threshold Judgment Coefficient Optimization Based on Constant False Alarm Rate

In radar signal detection system,the false alarm rate with a fixed threshold would be intensely increased when voltage of noise or clutter raised,at the same time,the probability of detection would be decreased.Therefore,in order to garantee a certain level of probability of detection,the constant false alarm rate method is applied.During the processing of constant false alarm rate in radar system,the intensity of clutter may possibly deflect the average value,thus the false alarm rate is increased intensely with theoretical judgment threshold coefficient.The performance of constant false alarm in radar signal detection is studied,the influence of finite number of range cells on the false alarm and probability of detection are analysed.An efficient algorithm to detect the practical judgment threshold in real-time,making radar system keep working in the constant false alarm rate state.