Optimized multistandard RF subsampling receiver architecture

Abstract

This paper presents a novel subsampling-based down-conversion topology for multistandard radio receiver design. This receiver topology is based on two subsampling stages. The first stage has a fixed RF subsampling frequency; however, the IF sampling frequency of the second stage is variable and depends on the standard being considered. This approach overcomes various undesirable effects related to the sampling frequencies and noise aliasing. By optimizing the choice of the RF subsampling clock frequency, complete multistandard RF bands are down-converted to the same IF band. Quadrature baseband channel downconversion is achieved by a tunable IF sampling frequencies clock. A tunable band-pass RF filter and an IF band-pass filter are designed to perform anti-aliasing and limit wideband noise. A generic design methodology is proposed and validated through its application to a GSM, UMTS and IEEE-802.11g multistandard receiver. Simulation results of this receiver design example confirm the validation of proposed subsampling receiver topology and show the efficiency of the design methodology.