一种镜像抑制双输出的微波光子信道化接收机

微波光子信道化接收机可将待接收的射频信号转化到光域进行传输和处理，有效避免了电子瓶颈的限制，可实现超大带宽信号或多频点信号的瞬时接收，非常适用于雷达系统和电子战。该文提出一种镜像抑制双输出的微波光子信道化接收机，信号路和本振路都采用光分路器分为3路，光本振利用声光移频器实现左右移频后与信号路进入镜像抑制混频器，最终可将一个6 GHz带宽的射频信号划分到6个带宽为1 GHz的子信道完成接收。该方案无须用到光频梳且信道化效率提高1倍，子信道的信道串扰均超过22 dB，镜像抑制比约为24 dB左右，系统的无杂散动态范围可达到106.7 dB·Hz 2∕3。

A Microwave Photonic Channelizer Based on Dual-output Image-reject Mixer

The microwave photonic channelizer can convert the Radio Frequency (RF) signal into the optical domain for transmission and procession, avoiding effectively the limitation of electronic bottleneck, and realizing the instantaneous reception of ultra-wideband signal or multi-frequency signals, which can be perfectly applied to radar system and electronic warfare. In this paper, a microwave photonic channelizer based on dual-output image-reject mixer is proposed, both the signal path and the local oscillator path are divided into three paths by using an optical coupler. An acousto-optic frequency shifter is used by the optical local oscillator to shift the frequency to the left and right and then enters the image rejection mixer with the signal path. Finally, a 6 GHz bandwidth RF signal is divided into 6 subchannels with a bandwidth of 1 GHz to achieve simultaneous reception. This scheme needs no optical frequency comb and doubles the channelization efficiency, the image rejection ratio of the sub-channels all exceeds 22 dB, and the spurious-free dynamic range of the system can reach 91.4 dB·Hz 2∕3.