Design Of X-band MMIC Broadband IQ Mixer

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 silicon germanium (SiGe) Microwave Monolithic Integrated Circuit (MMIC) has now become hot in the research area.IQ mixer is one of the most important modules in the communication system and it affects the performance of the communication system. In this dissertation, the principle of IQ mixer is studied and an X-band MMIC broadband IQ mixer is implemented using JAZZ 0.18μm SiGe BiCMOS process, which is prepared for the miniature X-band communication system.First of all, the present domestic and international research condition of MMIC IQ mixer is introduced in this dissertation. Secondly the commonplace JAZZ 0.18μm SiGe BiCMOS process components and their models are presented. After that the principle of mixer and the IQ mixer's theory of image rejection are introduced. Finally the detail design of X-band MMIC broadband IQ mixer's sub-modules and its schematic simulation are displayed.The IQ mixer which is designed in this dissertation achieves conversion gain of better than-9dB and image rejection of better than 30dB from 8 to 12GHz. The return loss of RF port and LO port are less than-8dB. The isolation between RF port and LO port is better than 45dB. The input P1dB and IIP3 are better than 12dBm and 23dBm, respectively. The magnitude imbalance and phase difference between the output ports are 0.2dB and 90°±2.3°, respectively.