Design and Analysis of a Programmable Receiver Front End With Time-Interleaved Baseband Analog-FIR Filtering

Abstract

This paper presents time-interleaving as an approach to improve the performance of programmable receiver front ends based on Filtering-by-Aliasing (FA). Using two parallel periodically time-varying paths, a sharp programmable filtering response is produced at RF, while achieving a good wideband S11. The implemented receiver achieved a filter stop-band suppression of 70dB with only 4×BW transition bandwidth, while S11 is better than -10dB throughout most of the LO range. Analysis for achieved S11 and noise figure are shown, while detailing methods to improve filtering performance in presence of important circuit parasitics. The effect of mismatches between time-interleaved paths is also analyzed and quantified.