机译:Comments on, Xuan Li, Shanghong Zhao, Zihang Zhu, Bing Gong, Xingchun Chu, Yongjun Li, Jing Zhao and Yun Liu 'an optical millimeter-wave generation scheme based on two parallel dual-parallel Mach-Zehnder modulators and polarization multiplexing', Journal of Modern Optics, 2015