Design And Implementation Of Wideband Microwave Photonic Mixing System

With the research and development of microwave photonics in recent years,it has a profound impact on RF systems and related technologies.Compared with the traditional radio frequency signal processing technology,microwave photonics derived from the microwave photon technology has the significant advantages of large bandwidth,strong flexibility and low loss,showing unprecedented superior performance.Therefore,the study of microwave photonic technology in radio frequency system has important theoretical value and significance.A broadband microwave photonic mixing system is designed and implemented in this paper.Firstly,the microwave photonic mixing technology is briefly introduced and analyzed in this paper.Next,this paper studies the existing microwave photon mixing scheme.Based on the parallel structure of the modulator,a hybrid frequency conversion scheme is designed,and the working principle of up conversion and down conversion is theoretically analyzed.At the same time,this paper uses the WinForm framework based on C#language and the STM32F746IGT6 model single chip based on Cortex-M7 architecture,and focuses on the design and function development of the control module of the broadband microwave photonic mixing system,mainly including two parts of the host computer software and the hardware.The central frequency of three programmable optical filters in the whole system can be controlled in real time by inputting the expected setting instructions in the upper computer interface.Compared with the set(control)assistant provided by the optical filter,the volume of the hardware part of the control module is only 5%,a total of 0.00015 m3;the overall power consumption of the module is only 15.2%,not more than 2.5W,and the central frequency of the 3 optical filters can be controlled in parallel through the 1 USB interfaces.In addition,the software part of this control module has the advantages of pre setting instruction,high function extensibility and rapid transplanting of code.This makes the upper and down functions of the whole system more flexible,maneuverable and faster.At the end of this paper,the control module is tested in several groups at first,and it is determined that the module can control the frequency of the optical filter in the frequency range of 193390GHz to 193425GHz.The function of up and down frequency conversion of the broadband microwave photonic mixing system is tested.According to the results,the integrated function of up and down frequency conversion,the noise coefficient and the overall performance of the system are determined to meet the requirements of this paper.