Research On Microwave Photonic Phase Shifting And Mixing Technology

The microwave mixer and phase shifting is a key technology in the phased-array beamforming networks for radar and satellite communication.Especially in the radar system,the technology has the advantages of strong anti-interference ability,large bandwidth,fast tuning speed,etc.,and overcomes the electronic bottleneck problem of the traditional microwave structure.It is necessary to simultaneously implement microwave mixer and phase shifting operation in beamforming,while most of the existing systems can only achieve a single down-conversion or phase shift,and there are few solutions for simultaneously implementing microwave mixer and phase shifting.This paper proposes a solution to achieve variable frequency phase shifting in the system.The main research contents of the thesis are as follows:(1)Firstly,the principle and application of optically controlled phased-array technology and mixing technology in the field of microwave photonics are expounded.Then,based on this,the realization methods of phase-shifting technology and mixing technology are summarized,and three modulation modes of external modulation are analyzed and deduced in detail.(2)Propose a scheme of microwave photonic phase shifters based on DPMZM and PM cascaded.Based on the existing schemes,a microwave photonic phase shifting scheme based on DPMZM and PM cascaded is proposed for improve the phase shift bandwidth and amplitude response of the phase shifter.The VPI is used to analyze the system,which proves that the scheme has the advantages of wide adjustable RF signal frequency,continuous tunable phase shift range,and basically unchanged output signal amplitude without using filter.(3)Propose the cascaded DPMZM microwave photonic mixing phase shifting technology scheme.This paper proposes a new phase-adjustable microwave photonic mixer scheme without using filter,which can realize frequency conversion and phase shift simultaneously in the system.This scheme achieves phase shifting in a large frequency range by adjusting the DC bias voltage in the PM.