A novel scheme is proposed to enlarge the spurious free dynamic range (SFDR) of microwave photonic (MWP) link by using dual-parallel Mach–Zehnder modulator, which modifies the single sideband signal and replaces the optical carrier with an unmodulated one to remove the optical main sources of third-order intermodulation distortion (IMD3). Simulation results show that the IMD3 and fifth-order intermodulation distortion can be suppressed greatly even when the modulation depth increases to a high value, and the link is limited by seventh-order intermodulation distortion and the SFDR is improved by 34.2 dB Hz in a 1-Hz bandwidth. The error vector magnitude of the MWP link with the proposed scheme is improved significantly for the transmitted 1-Gbit/s 16- quadrature amplitude modulation (QAM) signal.

提出了一种新方案，通过使用双并行马赫曾德尔调制器来扩大微波光子（MWP）链路的无杂散动态范围（SFDR），该调制器会修改单边带信号，并用未调制的光载波代替光载波以消除三阶互调失真（IMD3）的光学主要来源。仿真结果表明，即使调制深度增加到较高的值，IMD3和五阶互调失真也可以得到很大抑制，链路受到七阶互调失真的限制，SFDR在1阶中提高了34.2 dB Hz。 -Hz带宽。对于所发送的1-Gbit / s 16正交幅度调制（QAM）信号，采用所提出方案的MWP链路的误差矢量幅度得到了显着改善。