传统的星载变频通道存在易受电磁干扰、动态范围受限、带宽瓶颈等不足，将微波光子技术引入卫星通信系统中，体现出极大的技术优势，克服了电域信号变频的局限性，提升了星载变频通道的性能。本文提出了一种基于并联马赫-增德尔调制器(MZM)与相干接收的宽带微波光子变频技术, 通过采用相干接收方法，能够实现较好的共模噪声抑制并降低谐波失真的影响，同时结合抑制载波调制与光学本振信号带来的优势，有效改善了变频无杂散动态范围等指标。通过实验验证得到杂散抑制比优于60dB、无杂散动态范围优于100 dB?Hz2/3，为新型星载微波光子变频方案设计及实际应用提供了必要的理论依据与技术支撑。
The conventional frequency conversion of satellite payloads in electronic domain has the drawbacks such as susceptible to electromagnetic interference, limited spur-free dynamic range (SFDR), as well as narrow band. The introduction of microwave photonic has shown many interesting advantages, and can overcome the above limitation. As a result, it can greatly enhance the performance of the frequency conversion system. A broadband microwave photonic frequency conversion technology based on parallel Mach-Zehnder modulator (MZM) and balanced coherent heterodyne detection is proposed in this paper. The common mode noise and the harmonic distortions are suppressed by using balanced coherent heterodyne detection. In addition to the common noise suppression, the advantages brought by both the suppressed carrier modulation and the strong optical oscillator, can significantly improve the SFDR of the frequency conversion system. A spur suppression of 60dB, and a SFDR better than 100 dB?Hz2/3 in microwave photonic frequency conversion system is proposed and experimentally demonstrated. Essential theoretical basis and technical support are provided for the new scheme of microwave photonic frequency conversion of satellite payloads.