Discrete Dynamics in Nature and Society
Volume 2011 (2011), Article ID 356421, 9 pages
http://dx.doi.org/10.1155/2011/356421
Research Article

Multiscale KF Algorithm for Strong Fractional Noise Interference Suppression in Discrete-Time UWB Systems

Liyun Su,1 Yuli Zhang,1 Yanju Ma,1 Jiaojun Li,2 and Fenglan Li3

1School of Mathematics and Statistics, Chongqing University of Technology, Chongqing 400054, China
2School of Electronic Information and Automation, Chongqing University of Technology, Chongqing 400054, China
3Institute of Library, Chongqing University of Technology, Chongqing 400054, China

Received 26 July 2011; Accepted 4 September 2011

Academic Editor: Daniele Fournier-Prunaret

Copyright © 2011 Liyun Su 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.

Abstract

In order to suppress the interference of the strong fractional noise signal in discrete-time ultrawideband (UWB) systems, this paper presents a new UWB multi-scale Kalman filter (KF) algorithm for the interference suppression. This approach solves the problem of the narrowband interference (NBI) as nonstationary fractional signal in UWB communication, which does not need to estimate any channel parameter. In this paper, the received sampled signal is transformed through multiscale wavelet to obtain a state transition equation and an observation equation based on the stationarity theory of wavelet coefficients in time domain. Then through the Kalman filter method, fractional signal of arbitrary scale is easily figured out. Finally, fractional noise interference is subtracted from the received signal. Performance analysis and computer simulations reveal that this algorithm is effective to reduce the strong fractional noise when the sampling rate is low.