DocumentCode :
1971222
Title :
Nonstationary noise cancellation in infrared wireless receivers
Author :
Krishnan, Sridhar ; Fernando, Xavier ; Sun, Hongbo
Author_Institution :
Dept. of Electr. & Comput. Eng., Ryerson Univ., Toronto, Ont., Canada
Volume :
3
fYear :
2003
fDate :
4-7 May 2003
Firstpage :
1945
Abstract :
Infrared is attracting much attention for indoor wireless access due to its enormous bandwidth, inherent privacy and low cost. Intensity modulated, directly detected infrared schemes do not experience multipath fading. However, ambient noise due to artificial lighting has been the major concern in infrared wireless systems in indoors. Conventionally, static or low frequency noise due to conventional light sources is removed using optical high pass filters. Nonetheless, interference from fluorescent lights equipped with electronic ballasts has periodic interference components up to 1 MHz and, cannot be filtered easily. In this paper, soft DSP filters are proposed to cancel the harmonics, ambient noise, and uncorrelated signal structures. Nonstationary noise is cancelled with an adaptive denoising filter, and a comb filter cancels interference from the electronic ballasts. Adaptive soft filters have the advantage that they can be easily updated and track the variations in noise characteristics. Simulation results show promising improvement in noise cancellation even under very low and varied SNR and noise source conditions.
Keywords :
adaptive filters; comb filters; interference suppression; optical noise; optical receivers; adaptive denoising filter; adaptive filters; comb filter; electronic ballasts; infrared wireless receiver; noise cancellation; nonstationary noise; soft DSP filters; wavelet-packets; Adaptive filters; Bandwidth; Electronic ballasts; Infrared detectors; Interference cancellation; Low-frequency noise; Noise cancellation; Optical filters; Optical noise; Optical receivers;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Electrical and Computer Engineering, 2003. IEEE CCECE 2003. Canadian Conference on
ISSN :
0840-7789
Print_ISBN :
0-7803-7781-8
Type :
conf
DOI :
10.1109/CCECE.2003.1226295
Filename :
1226295
Link To Document :
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