Design Of Ka-band Image-Reject Down-Converter MMIC

Recently, due to the processing advancements and electronic circuit developments, the communication system shows reduced size and cost with higher reliability to meet the needs of today's markets. Therefore, the Microwave Monolithic Integrated Circuit (MMIC) has now become hot in the research area.Down-converter is one of the most important modules in the communication system and there is always an interest for research on size miniaturization of the integrated MMICs. This paper discusses the total design flow of Ka-band image-reject down-converter MMIC. The principles of image-reject down-converter MMIC design, the design of sub-harmonic image-reject mixer and LNA, the EM simulation and test result are introduced. The simulation and measurement results show that this image-reject down-converter is leading in China.The Ka-band image-reject down-converter MMIC design based on 0.15μm GaAs pHEMT process which provided by WIN semiconductors corp. First of all, the present domestic and international research condition of down-converter MMIC is introduced in this dissertation. Secondly the commonplace MMIC components and their models are presented. Thirdly, several basic structures of down-converter, detailed analysis of the design in the case and some innovations are discussed. After that the principle and detail design of main modules-LNA and sub-harmonic image-reject mixer are introduced. EM simulation and test results are presented. Finally the simulation results of the down-converter are displayed.The image-reject down-converter MMIC which is designed in this dissertation achieves conversion gain of better than 11.5dB, image rejection above 20dB and noise figure of better than 4dB for the RF frequency from 32-38GHz. The port isolations are better than 30dB. The input P1dB is better than -20dBm.