基于功率合成的微波系统设计与实现OA

[Background]With the continuous advancement of microwave electronic technology,research on power combining technology has attracted increasing attention.Power combining based on conventional vacuum devices such as klystrons represents a typical application case of power combining technology in microwave source systems.However,existing power combining technologies struggle to achieve two functions simultaneously without dismantling or replacing the transmission waveguide:enabling a single klystron to operate independently for microwave power output,and allowing two klystrons to work concurrently at the center frequency to produce combined microwave power output.[Purpose]In view of the application requirements of a high-power microwave system,this paper presents a microwave radiation system adopting conventional Ku-band klystrons as power sources.[Methods]To achieve this goal,a solid-state pre-stage excitation source is adopted,which outputs two power channels A and B.It can feed excitation signals to a single klystron separately or supply excitation signals to two klystrons simultaneously,integrating the two klystrons into a unified microwave source.A power combiner and a polarization conversion mechanism are deployed.Without disassembling or replacing the transmission waveguide,the system enables a single klystron to operate independently to output microwave power.Meanwhile,the polarization conversion mechanism adjusts the rotation angles of two cascaded circular polarizers by regulating three rotary joints,thereby realizing conversion between horizontally and vertically polarized incoming waves,whether linearly polarized or circularly polarized.[Results]The results show that when a single klystron operates,the maximum output power reaches 0.61 MW within a bandwidth of hundreds of megahertz.When two klystrons operate simultaneously,their respective output powers at the center frequency are 0.53 MW and 0.56 MW,with a combined power of 1.04 MW.A standard microwave receiving antenna is mounted 2.7 m directly in front of the microwave antenna,and the maximum measured electric field strength is 32 kV/m.[Conclusions]Therefore,the designed microwave radiation system can achieve microwave power output by a single klystron operating independently without removing or replacing the transmission waveguide.Meanwhile,it supports simultaneous operation of two klystrons at the center frequency to output microwave power through power combining,with a power combining efficiency exceeding 95%.This work provides a valuable reference for further research on high-power microwave power combining technology.