一种可重构的微波光子混频移相系统

A Reconfigurable Microwave Photonic Mixing and Phase Shifting System

提出了一种可重构的微波光子混频移相系统,通过调节本振信号频率及检偏器角度,可输出上/下变频微波信号,同时其相位可在360°范围内连续调节。此外,适当改变任意两个混频通道间的相位差,可重构实现I/Q混频、双平衡混频和镜像抑制混频,应用于多通道时可输出多频段混频移相微波信号,并且每个通道的相位可独立调节。由于让本振信号的高阶边带参与混频,成倍降低了对本振信号频率的要求。仿真结果表明,当本振信号和射频信号频率分别为10 GHz和19 GHz时,系统的混频范围为1~79 GHz,相移幅度差低于0.1 mV,镜像抑制比超过65 dB,多频段混频后的信号功率差低于0.2 dB;90°电移相器、偏振控制器角度调节偏差几乎不影响系统性能,且合适的射频信号功率有助于提高系统性能。理论分析和仿真验证了该系统具有较高的灵活性、重构性和实用性。

A reconfigurable microwave photonic mixing and phase shifting system is proposed.By adjusting the frequency of the local oscillator signal and the angle of the polarizer,it can output up/down conversion microwave signal,and its phase can be adjusted continuously within 360°.In addition,by appropriately changing the phase difference between any two mixing channels,it can be reconstructed to realize I/Q mixing,double-balanced mixing and image rejection mixing.When applied to multiple channels,it can output multi-band mixing and phase-shifted microwave signal,and the phase of each channel can be adjusted independently.Since the high-order sidebands of the local oscillator signal are involved in the mixing,the requirements for the frequency of the local oscillator signal are reduced exponentially.The simulation results show that when the frequency of the local oscillator signal and the RF signal are 10 GHz and 19 GHz respectively,the mixing range of the system is 1~79 GHz,the phase shift amplitude difference is less than 0.1 mV,the image rejection ratio exceeds 65 dB,and the signal power difference after multi-band mixing is less than 0.2 dB.In addition,the 90°electrical phase shifter and polarization controller angle adjustment deviation hardly affect the system performance,and the appropriate radio frequency signal power can help improve the system performance.Theoretical analysis and simulation have verified that the system has high flexibility,reconfiguration and practicability.