A comparison of analog and digital circuit implementations of lowpower matched filters for use in portable wireless communicationterminals

摘要

In this paper, analog and digital circuit realizations of anparallel programmable matched filter are examined. Through widenvariations of the design space parameters, the general trend that isnobserved is that short, fast circuits tend to favor an analognimplementation, while longer, slower circuits make a digitalnimplementation more appropriate. A methodology is provided for choosingnthe preferable circuit-implementing technology when power consumption-asna function of data precision, filter length, operating frequency,ntechnology scaling, and the maturity of the fabrication process-is usednas the primary metric of comparison. It is shown that neither the analognnor the digital matched filter implementation is universally more powernefficient than the other. Rather, a surface is mapped in thenmultidimensional design space where, on one side of this surface, andigital solution is preferable, while on the other side of the surface,nan analog circuit is appropriate. Equations are given which delineatenthe position of this transitional surface in terms of the design spacenparameters, and example calculations and plots depicting the regions ofndominance for the digital and analog matched filters for specificnprocess and system parameters are presented