A 0.7 – 3.7 GHz six phase receiver front-end with third order harmonic rejection

Abstract

This paper presents a highly linear receiver front-end operating from 700 MHz to 3.7 GHz with 3rd order harmonic rejection. It consists of a complementary low noise transconductance amplifier with capacitive cross coupling and negative gm current sources, a six phase current-mode passive mixer, and baseband transimpedance amplifiers providing programmable gain. The circuit has been fabricated in 65 nm CMOS technology with an active area of just 0.09 mm2. It consumes 7.2 mA, excluding the six phase local oscillator generation, from a 1.2 V supply, achieving a third order harmonic rejection of 40 dB, and a noise figure of 3 to 4.5 dB at 52 dB gain. The out of band IIP2 and IIP3 at full gain is +55 dBm and +5 dBm, respectively.