Research On Millimeter-wave Power Synthesis Amplifier Based On TE₂₀ Mode

Power amplifier is the key device of millimeter wave communication system,However,in the millimeter-wave band,the output power of a single solid-state device often fails to meet the system requirements.The research on power combining technology is particularly important.In this thesis,a waveguide form with low transmission loss is used to study the Ka-band and W-band power combination amplifier based on TE₂₀ mode.The content is as follow:1.The transition theory of waveguide to microstrip in millimeter wave band is studied.In the Ka and W bands,a waveguide to microstrip dual probe transition structure based on the TE₂₀ mode is designed.By using the isolation of TE₂₀ mode and the transmission conditions of over-mode waveguides to solve the problems of the traditional microstrip dual probe transition structure has an isolation of only-6d B and insufficient space for installing two chips and its power supply circuit.2.Based on the field analysis of the TE₂₀ mode,the TE₁₀-TE₂₀ mode conversion structure is studied.In the Ka and W bands,an improved TE₁₀-TE₂₀ mode converter based on vertical excitation is designed.3.In the Ka band,power combiners such as coplanar wall magic T based on ridge waveguide,E-plane branch waveguide bridge are designed,and the TE₂₀ mode power divider based on the E-plane branch waveguide bridge is also studied.In the W band,power combiners such as waveguide ring bridges and H-plane branch waveguide bridge are designed.The coplanar wall magic T based on ridge waveguide in the Ka band and the H-plane branch waveguide bridge in the W band were processed and tested.At the same time,transition structures of H-E plane waveguides in Ka-band and W-band were developed.4.The power of AMMC6345 monolithic power amplifier in Ka-band is tested.The combining structure uniting with coplanar wall magic T based on ridge waveguide,modified TE₁₀-TE₂₀mode converter,waveguide to microstrip dual probe transition structure based on the TE₂₀ mode and H-E plane waveguide transition structure is selected to realize 4-way power combining.The final test results show that in the frequency range of 29-36.5GHz,the efficiency of the combiner is higher than 80%,the maximum output power is 31.03d Bm at35GHz,and the maximum combining efficiency is 89%at 31GHz.5.The power of BAL-WPA monolithic power amplifier in W-band is tested.The combining structure uniting with H-plane branch waveguide bridge,modified TE₁₀-TE₂₀mode converter and waveguide to microstrip dual probe transition structure based on the TE₂₀mode is selected to realize 4-way power combining.The final test results show that in the frequency range of 77-100GHz,the efficiency of the combiner is higher than 77%,the maximum output power is 26.36d Bm at 85GHz,and the maximum combining efficiency is90%at 87GHz.