Mixer Chip For The Applications Of Satellite Navigation Receiver Design

With the rapid development of wireless communication, it makes a high requirement of RF front end circuit. Such as low power, small size, highly integrated. System on Chip (SoC) has become the main focus of wireless communication area. The structure and the performance of the RF receiver will directly affect the entire communication system.Based on the receiver RF front end of the satellite navigation system, two active image rejected mixers(IRM) applying in a low-IF receiver system, which works under the L-band and S-band respectively are designed using the JAZZ 0.35um SiGe BiCMOS process.In this paper, the advantage of low-IF receiver structure and the characteristic of JAZZ 0.35um SiGe BiCMOS are introduced firstly; Secondly, the principal, the classification and the specification of IRM, compares different types of mixers and finally chooses the topology of Gilbert mixer according the system specification. The thesis analyzes the linearity, conversion gain, noise figure, isolation and etc. affected by the topology. Because the linearity is the most important specifications of a mixer, several linearization design techniques for Gilbert mixer are discussed.The IRM is composed of a quadrature down-conversion mixer which is based on the double-balanced Gilbert cell followed a polyphase filter, which are connected by an emitter follower for the voltage match.The S-band IRM exhibits 15.34dBm of IIP3, an image rejected ratio of above 42dB and a 19.81dB of SSB noise figure and consumes only 7.75mA of current from a 3.3V power supply under 27℃condition. The L-band IRM exhibits 15.31dBm of IIP3, an image rejected ratio of above 40dB and a 21.19dB of SSB noise figure and consumes only 7.46mA of current from a 3.3V power supply under 27℃condition.