DocumentCode :
3618239
Title :
Time-frequency channel modeling and estimation of multi-carrier spread spectrum communication systems
Author :
S. Senay;A. Akan;L.F. Chaparro
Author_Institution :
Dept. of Electr. & Electron. Eng, Yeditepe Univ., Istanbul, Turkey
Volume :
3
fYear :
2005
fDate :
6/27/1905 12:00:00 AM
Abstract :
In wireless communications, the channel is typically modeled as a random linear time-varying system that spreads the transmitted signal in both time and frequency due to multipath and Doppler effects. In this paper, we show how time-frequency analysis can be used to model and estimate the channel of a multi-carrier spread spectrum (MC-SS) system with a complex quadratic spreading sequence. We show that in this case the effects of time delays and Doppler frequency shifts can be characterized effectively as time-shifts. Using the discrete evolutionary transform (DET) we are able to estimate these effective time shifts via a spreading function and use them to equalize the channel. To illustrate the performance of the proposed method we perform several simulations with different levels of channel noise, jamming and Doppler frequency shifts.
Keywords :
"Time frequency analysis","Spread spectrum communication","Fading","Doppler shift","Delay effects","Discrete transforms","Jamming","OFDM","Communication channels","Chirp"
Publisher :
ieee
Conference_Titel :
Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP ´05). IEEE International Conference on
ISSN :
1520-6149
Print_ISBN :
0-7803-8874-7
Type :
conf
DOI :
10.1109/ICASSP.2005.1415817
Filename :
1415817
Link To Document :
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