基于似然比检验的红外小弱目标快速航迹起始方法

Infrared dim target track initiation method based on likelihood ratio test

利用红外测量跟踪系统获取目标信号幅度信息,提出了一种基于序列似然比检验的小弱运动目标航迹快速起始方法。用动态2维分配算法关联"量测-航迹",采用序列似然比检验衡量航迹质量,一旦似然函数比达到阈值则确认目标航迹。该方法可根据目标信噪比不同采取不同帧数来起始、确认目标航迹,做到信噪比越大起始帧数越少,目标航迹检测概率越高,而信噪比越小则起始帧数越多。理论分析和试验结果表明,该方法既能提高航迹起始速度,又能提高目标航迹检测概率,避免和解决了M/N逻辑法需要固定扫描帧数才能确认航迹的局限性。

An approach based on sequential likelihood ratio test is presented to rapidly initiate track for dim moving target using the target amplitude acquired by the infrared tracking system. The two-dimensional dynamic assignment algorithm is adopted firstly to associate measurement with track, and the sequential likelihood ratio test is then taken to evaluate the quality of track. The target track is confirmed immediately once the likelihood ratio is greater than the threshold. This approach can take different scans to initiate target track according to the signal-to-noise ratio（SNR） of target, and the bigger the SNR of target is, the less frame it needs to achieve a given track detection probability. Some experiments are included and the results show that this approach can improve the speed of track initiation and enhance the detection probability of target track, without the limitation of the M/N logical method that the number of scans must be fixed to initiate target track with different SNRs.