Design and Performance Analysis of Mixer Based on Microwave Photonic Frequency Conversion Technology

Microwave photonic links have the advantages of high transmission quality, low power consumption, strong anti-electromagnetic interference ability and wide dynamic floating range, and are widely used in radar, satellite, measurement and wireless communication networks. In this article, the Mach-Zehnder modulator is selected as the basic model of microwave photonic frequency conversion technology. The performance of the model is analyzed, including the optical gain, dynamic range and noise index. Mach-Zehnder modulator is applied to all-optical mixing technology of wide-band microwave signal in series and parallel, and a mixer based on Mach-Zehnder modulator is designed. The mixer takes advantage of the characteristics of microwave photon technology, realizes the conversion of light-borne signal to intermediate frequency/baseband signal, thus greatly reducing the difficulty of subsequent processing and hardware requirements. From the point of view of optical signal transmission, Mach-Zehnder modulator is used as the basic component. Multiple optical signal transmission node is used, that is, in series; upper and lower optical carriers are also used to achieve optical signal transmission, that is, in parallel. This way converts the optical signal into I-channel signal and Q-channel signal, and thus, it is conducive to the post-processing of optical signals. In the process of experiment, the error analysis of optical signal transmission and distortion analysis of signals of the designed mixer are conducted. Through a large number of experiments, it is proved that the mixer can reduce the transmission error and suppress the distortion of signal demodulation.