Effect of interpolation on PWVD computation and instantaneous frequency estimation

Sekhar, Chandra S and Sreenivas, TV (2004) Effect of interpolation on PWVD computation and instantaneous frequency estimation. In: Signal Processing, 84 (1). pp. 107-116.

PDF sdarticle.pdf Restricted to Registered users only Download (447kB) | Request a copy

Abstract

The peak of the polynomial Wigner–Ville distribution (PWVD) can be used for estimating the instantaneous frequency (IF) of monocomponent polynomial phase signals. However, the PWVD kernel, optimized to yield a time–frequency distribution (TFD) localized along the IF, comprises of fractional-time-sampled signals. When implemented in a discrete-time scenario, this calls for signal interpolation. We study three interpolation schemes—linear, cubic polynomial and sinc and derive expressions for the variance of the interpolated samples in the presence of noise. In representing nonstationary signals using the PWVD, the instantaneous energy content of noise auto-terms and signal-noise cross-terms is found to be the least for linear interpolation scheme. For polynomial IF estimation using the peak of the PWVD, it was found that linear interpolation is a computationally efficient way of obtaining reasonably good estimates at low signal-to-noise ratios (SNRs). For high SNRs, sinc interpolation outperforms the other two schemes. Similar results were found when the experiment was extended to sinusoidal IF signals also.

Item Type:	Journal Article
Publication:	Signal Processing
Publisher:	Elsevier
Additional Information:	Copyright of this article belongs to Elsevier.
Keywords:	Interpolation;Polynomial Wigner–Ville distribution;Instantaneous frequency
Department/Centre:	Division of Electrical Sciences > Electrical Communication Engineering
Date Deposited:	28 Mar 2007
Last Modified:	19 Sep 2010 04:36
URI:	http://eprints.iisc.ac.in/id/eprint/10283

Actions (login required)

View Item