Research On Microwave Solid-state Broadband Power Combination

Recently,solid state power devices with its better performance are gradually replacing electronic vacuum devices,being the high power emitter in electronic countermeasures,communications and radar systems.Therefore,the solid state high power combining technique using MMIC PAs has increasingly become a research hotspot in the field of microwave and millimeter wave.How to realize a high efficieney and a broad bandwidth while maintaining a high power capacity of the power combiner is the key technical challenge.These problems are deeply studied in this thesis.The mainly achievements are described below:Firstly,the basic principle of solid state power combining technology and its classification are introduced.Meanwhile,how does the loss of circuit and the inconsistency of the amplitude and phase impact on the combining efficiency are analyzed,which builds a theoretical foundation for high efficiency wideband solid-state power combing.A broadband magic T based on dual ridge-waveguide is proposed.The simulation results show that within 8-18 GHz,the reflection coefficient of the input port is less than-15dB;the isolation between the E arm and H arms is greater than 48dB;the isolation between the direct arms is better than 15dB;the total insertion loss is less than 0.13 dB.A technical scheme to achieve broadband radial power combining is proposed,which takes full advantages of the wide-band characteristics of the ridge waveguide and the coaxial.Under the guidance of this design idea,two broadband power combiners of 2-6GHz and 6-18 GHz are designed and manufactured.The coaxial input port of these two power combiners can both be connected directly with the standard coaxial connector;the output ports have been converted to the microstrip line and can be connected directly with the amplifier chip.The test results show that as for the 2-6GHz power combiner,within the operation band,the input port return loss is better than 15 dB,and the insertion loss is less than 1dB;as for the 6-18 GHz power combiner,the working frequency band has been expand to 4-19 GHz,where the reflection coefficient at the coxial port is less than-10 dB,and the insertion loss is less than 2dB.