声光偏转效应在相干光检测的应用

为使现代电子侦察技术能适应信号密集、宽频谱、大动态的电磁环境, 提出了一种基于声光偏转器实现相关光信号处理的方法, 分析了射频信号频率变化与布拉格衍射角的关系, 讨论了声光偏转效应对信号频率的空间滤波特性; 在理论分析的基础上, 构建了在可见光范围内实现声光偏转的相干光信号探测的实验系统, 并通过计算机仿真对比, 验证了这种方法的可行性。实验表明, 采用波长为630 nm的单频激光, 带宽为200 MHz的声光偏转器, 其频率分辨率优于1 MHz, 频率信号的空间分离效果明显, 接收灵敏度和信噪比得到改善。

Application of Coherent Optical Detection Technology Based on Acousto-optic Deflecting Effect

To adapt modern electronic reconnaissance techniques to the electromagnetic environment of dense signal, broadband spectrum, and large dynamic range, a coherent optical signal processing method based on acousto-optic deflector is presented. The relationship between the changes of radio-frequency signal frequency and Bragg diffraction angle is analyzed, spatial filtering characteristic resulted from acousto-optic deflection effects is discussed. On the basis of theoretical analysis, the experimental system using acousto-optic technique is established to achieve coherent optical signal detection in the visible light range. The feasibility of this method is proved by computer simulation results. Experimental results show that if the system uses a single-frequency laser with wavelength of 630 nm and a acousto-optic deflector with bandwidth of 200 MHz, the frequency resolution is better than 1 MHz, the space separation effect of frequency signal is obvious, and the received sensitivity and signal-to-noise ratio (SNR) are improved.