Adaptive switched capacitor filters based on the LMS algorithm

Author

Menzi, Ulrich ; Moschytz, George S.

Author_Institution

Inst. for Signal & Inf. Process., ETH, Zurich, Switzerland

fYear

1990

fDate

1-3 May 1990

Firstpage

2220

Abstract

An approach to implementing an adaptive FIR (finite-impulse response) filter based on the LMS (least-mean-square) algorithm using SC (switched-capacitor) circuits is described. A concept for such a realization is presented, consisting of the following basic elements: delay element, summer, integrator, and multiplier. The influence of nonideal effects of SC networks on the behavior of the filter is investigated in an error analysis. It is shown that nonidealities in the FIR filter part can be eliminated by an additional constant tap element, whereas the main error source in the adaptation part is the integrator offset errors, which can be eliminated by offset-free SC integrators

Keywords

adaptive filters; error analysis; filtering and prediction theory; least squares approximations; network analysis; switched capacitor filters; LMS algorithm; SC networks; active filters; adaptive FIR filter; additional constant tap element; error analysis; finite-impulse response; integrator offset errors; least-mean-square; nonideal effects; offset-free SC integrators; switched capacitor filters; Adaptive filters; Adders; Capacitors; Circuits; Delay; Finite impulse response filter; Information processing; Least squares approximation; Signal processing; Wiener filter;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 1990., IEEE International Symposium on

Conference_Location

New Orleans, LA

Type

conf

DOI

10.1109/ISCAS.1990.112314

Filename

112314