Design of radio frequency integrated circuit (RFIC)

Abstract

Recent years have seen a growing market demand for RFID (Radio Frequency Identification) products. In order to provide compact hardware solution, RF front-ends need to be implemented in integrated circuits or so called RFIC. One of the most important components of the RF front-end architecture is the mixer, which is used for frequency translation. Since RFID products must cope with signals of various power levels, mixers must exhibit high linearity and wide dynamic range. In this project, design of highly linear Gilbert cell active mixer is investigated. In particular, a modified differential active bias is proposed to improve mixer linearity as well as dynamic range. Effects of active bias technique are examined by comparing performance of mixers using active bias with that of mixers using conventional bias. Simulation results show a maximum 12dB improvement in input referred 1dB gain compression point and a maximum 6.3dB improvement in output referred 1dB gain compression point. Besides, the linearity and dynamic range improvement does not incur significantly degraded noise performance. In addition, the active bias requires no additional DC power while consumes little chip area.