提出一种使用功率谱相减的实时联合变换相关器作多目标检测。使用这种方法,输入面有两套联合图像。在第二套联合图像中,参考图像是对比度反转的。使用衍射光栅对这两套联合功率谱作相减处理,这种方法可大大抑制输出面的直流项及不想要的伪相关峰,增强相关峰的强度、锐度和峰噪比,提高抗噪声干扰的能力,从而提高对多目标检测的准确度。给出对具有灰度级的多目标输入景物的计算机模拟结果和光学实验结果。实验结果证实了该系统设计及性能分析的正确性。

Multitarget detection using a real time joint transform correlator with power spectrum subtraction is proposed. It has two joint images in the input plane. In the second joint image, the reference image is contrast reversal. The two joint power spectra are subtracted using a diffraction grating. The D.C. term and undesired terms are substantially suppressed by this technique. It can yield strong auto correlation peak intensity, sharp auto correlation peak width, big peak to noise ratio, and the high capability of anti-background noise. Thus it produces higher accuracy of detection. Computer simulation results and optical implementation for input scences of the gray-scale multitarget are given. The experimental results have verified the correctness of the system design and performance analysis.