A Discrete-Time Mixing Receiver Architecture with Wideband Image and Harmonic Rejection for Software-Defined Radio

Abstract

A discrete-time mixing architecture for software defined radio receivers is proposed. It exploits 8x RF voltage oversampling followed by charge domain weighting to achieve 40dB 3rd and 5th harmonic rejection without channel bandwidth limitations. Also noise folding is reduced by 3dB. A zero-IF downconverter chip in 65nm CMOS can receive RF signals up to 900MHz, with NFmin=12dB, IIP3=11dBm at <20mW power consumption including multi-phase clock\ud generation