对光外差法生成微波/毫米波技术中的偏振失谐进行了分析.首次推导出偏振失谐对微波,毫米波功率影响的计算公式.利用自行制作的基于双波长保偏光纤光栅激光器的微波/毫米波发生器生成30GHz左右的微波/毫米波信号,其偏振失谐的实验结果与理论分析结果一致,证明了理论分析的正确性.最后,应用分析结果模拟仿真了偏振失谐对60GHz毫米波信号的影响,得出了不同情况下系统的误码率及不同传输距离下的眼图.结果表明,在光纤无线传输链路中采用偏振失谐控制技术会大大提高链路的可靠性,在对链路进行偏振失谐控制的前提下,传输30km仍可保持误码率10-9以及很好的眼图,说明了偏振失谐控制的重要性.
In this paper, we study the effect of polarization mismatch (POM) in micro/millimeter-wave (mm-wave) generation employing optical self-heterodyning technology. The calculation formula of POM-induced mm-wave power penalty is derived for the first time. Utilizing a mm-wave generator based on a homemade dual-wavelength polarization maintaining fiber grating laser, several mm-wave with frequency around 30 GHz is generated. The experimental results accord well with the theoretical ones, which can prove that the theoretical analysis is correct. Finally the simulation of effect of POM on 60 GHz is performed. Under different conditions, the bit error rates (BERs) and the eye diagrams are obtained. BER below 10-9 and clear eye diagrams can be obtained if the POM is under control. So it is very important to control the POM in fiber-optic wireless link.