Research On V-band Power Combining Amplifier Based On Radial Waveguide

Aiming at the demand of satellite communication for millimeter wave power amplifier,a design scheme of V-band power amplifier is proposed,and the feasibility is verified by simulation and test.Firstly,based on the comparison of the performance of TWTA and SSPA and the research of power combining technique,we choose high power amplifier as the basic unit circuit combining with high efficiency and low loss radial waveguide power combining network to achieve V-band high power output.The scheme has the advantages of low loss,and good amplitude and phase consistency.Secondly,two kinds of rectangular waveguide-circular waveguide TE01 mode converters are proposed in this paper.On the basis of the traditional Marie mode converter,a V-band Marie mode converter based on the principle of gradient mode is proposed.The simulation results show that in the range of 50-75GHz,S11 is below-25dB,and the suppression of other low order modes in circular waveguide is up to 40dB.The second structure based on the E-T junction feed network is a mode converter which is easily machined.The simulation results show that in 52-68GHz,the return loss is lower than-19dB,and the suppression of other low order modes is 30dB.The feasibility of the mode converter is verified by the measurement results,and how to expand its bandwidth is discussed.Then,a design of a 16-way radial waveguide power combining network based on circular waveguide is proposed.The simulation results show that the return loss is less than-20dB in the range of 50-75GHz.Cascading with the mode converter,the simulation results show that the return loss is less than-17dB in 52-68GHz.The measured results verify the feasibility of the radial power divider/combiner,and then how to improve the isolation between output ports is discussed.Finally,a V-band microstrip-rectangular waveguide transition structure based on the ridge waveguide is designed.The simulation results show that the S11 is lower than-20dB at the entire V band.The transition structure is processed and tested,combing with the active MMIC.the test results verify the feasibility.Based on the research of V band power amplifier,the key technologies of waveguide mode conversion,multi-path radial waveguide power combing,microstrip waveguide transition are studied.