Table of Contents
International Journal of Microwave Science and Technology
Volume 2009, Article ID 758783, 10 pages
Research Article

A Discrete-Time Downsampling FIR Filter for Windowed Integration Samplers

1Analog and Mixed Signal Center (AMSC), Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77843, USA
2Army Research Laboratory, AMSRD-ARL-CI-NT, Adelphi, MD 20783, USA

Received 1 September 2009; Revised 15 November 2009; Accepted 16 December 2009

Academic Editor: Liang-Hung Lu

Copyright © 2009 Karthik Raviprakash et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


A novel technique to reduce die area on a discrete-time 2 filter for charge sampling is proposed. An SNR comparison of the conventional and the proposed topology reveals that the new technique saves 25% die area occupied by the sampling capacitors of the filter. The idea is also extended to implement higher downsampling factors, and greater percentage of area is saved as the downsampling factor is increased. The proposed filter also has the topological advantage over previously reported works of allowing the designers to use active integration to charge the capacitance, which is critical in obtaining high linearity.