A 500MHz– 2.7 GHz 8-path weaver downconverter with harmonic rejection and embedded filtering

Abstract

This paper describes a combination of a Weaver mixer and an N-path filter for a superheterodyne receiver with a reconfigurable frequency plan. It uses an N-path topology driven with two different frequencies, effectively realizing a frequency shift together with band-pass filtering. To reduce transfers via harmonics other than the fundamental, a harmonic rejection scheme is used. A 28nm FDSOI CMOS implementation with 30 dB harmonic rejection and an out-of-band IIP3 of >20dBm is demonstrated.