abstract:This paper describes the design of a fully-integrated 5.2GHz CMOS RF transmitter circuit. This transmitter contains a quadrature up conversion mixer, a quadrature voltage-controlled oscillator (QVCO), and a class AB power amplifier (PA). Current reuse technique is used to increase the linearity and conversion gain of the mixer. The power amplifier is designed to provide 20.87 dBm maximun output power and 21.4% maximum power added efficiency. A quadrature mixer shows the simulated result of 0.15 dBm P1dB, 3.48dB conversion gain, and 10.37dBm IIP3. The LO is implemented by a quadrature voltage controlled oscillator (QVCO). This transmitter was designed with TSMC 0.18um 1P6M process.