基于双调制的反伪装目标探测系统研究

为了实现对被伪装网覆盖的被测目标进行有效探测,提高目标识别系统的反伪装能力,设计了基于电光和磁光双调制的目标识别系统。系统由起偏器、电光调制电路、磁光调制电路、检偏器、光电探测器等组成。推导了基于电光调制与磁光调制组合形成的调制函数,并在矢量分析的基础上,计算了电光调制参数δ与磁光调制参数θ对回波光强函数的影响。实验以边长1m的正方形钢板为测试目标,与两种常用伪装网配合在不同背景环境中进行反伪装目标探测。对不同偏振角条件下的回波光强响应电压进行了测试与分析。结果显示,目标与伪装网均存在明显的响应峰值,但由于目标位置及角度不同峰峰值位置有所不同,而背景不存在较强的响应值。故在整个磁光调制周期内,可以获得响应电压极值信号,从而识别伪装目标。对不同波长条件下的回波光强响应电压进行测试可知,光源波长的改变对回波峰峰值与背景噪声具有一定的影响,从而可以通过适当的调节光源波长实现提高目标图像信噪比的目的。总之,该系统在目标有伪装网覆盖的条件下仍能较好地区分目标及背景,具有很好地反伪能力。

Research on Target Recognition System for Camouflage Target Based on Dual Modulation

In order to achieve effective detection target c overed by camouflage nets,and to improve recognition ability to camouflage targ et,a target recognition system was designed based on the electro-optical and m agneto-optical dual modulation.The system was composed of polarizer,electrooptical modulation module,magneto-optical modulation module,analyzer,photoel ectric detectors and other components.It produced the modulation function combi nation of electro-optical modulation and magneto-optical modulation,and the c omposite modulation function was derived.On the basis of vector analysis,the i mpact of the function of the intensity of echo light was analyzed with the modul ation parameters for electro-optical and magneto-optical.In the experiment,a square steel side length of 1m was used as the test target,and two kinds of co mmonly camouflage nets were used for target detection in different background en vironments.Under different polarization angles conditions,the response voltage of echo light was tested and analyzed.Experimental results show that there are obvious response peak for the target and camouflage nets,however,because of t he different position and angle of the target,the peak position is different.A t the same time,the intensity of echo light from the background can not generat e a strong response voltage.Therefore,the extreme signal of response voltage c an be obtained to identify a camouflaged target in the entire magneto-optical m odulation cycle.As for wavelength variable experiments,it had a certain influe nce for echo peak and background noise caused by the changes of the light source wavelengths.Therefor,it can be adjusted by the source wavelength increasing t he SNR of target image.In short,the system has a good recognition ability for camouflage target.