Masters Theses

Author

Tyrone Reid

Date of Award

5-1993

Degree Type

Thesis

Degree Name

Master of Science

Major

Electrical Engineering

Major Professor

Bruce W. Bomar

Committee Members

Roy Joseph, L. Montgomery Smith

Abstract

The focus of this thesis is the elimination of constant-input limit cycles in fixed-point implementation of digital filters. Methods are discussed that produce state-space realizations free of limit cycles under constant-input conditions from realizations free of limit cycles under zero-input conditions. The first issue that was addressed is whether a realization free of limit cycles under zero-input conditions can have limit cycles under constant-input conditions. Computer simulations were presented to show that realizations free of zero-input limit cycles can have constant-input limit cycles. Four transfer functions which have constant-input limit cycles were selected for subsequent study. Implementations of these transfer functions on a Motorola DSP56000/1 family of digital signal processors were considered. By implementing these transfer functions on a Motorola DSP56000/1 simulator, it was verified that constant-input limit cycles are eliminated from the four transfer functions. To measure the computational cost of eliminating limit cycles, the limit-cycle-free implementations were compared to implementations that support limit cycles. The comparison was based on the number of processor instruction cycles required per sample processed.

Files over 3MB may be slow to open. For best results, right-click and select "save as..."

Share

COinS