Title :
EM-based acquisition of DS-CDMA waveforms for radiolocation
Author :
Iltis, Ronald A. ; Kim, Sunwoo ; Thomas, Anne
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Santa Barbara, CA, USA
Abstract :
A handshaking protocol for radiolocation is considered using DS-CDMA packet transmission. The expectation-maximization (EM) algorithm is employed for code delay acquisition. It is shown that the systematic application of EM on the flat-fading channel yields a parallel interference cancellation (PIC)-based technique for acquisition. On the frequency-selective channel, it is necessary to jointly estimate both the code delays and multipath coefficients. The EM approach in this latter case yields an algorithm that combines PIC with an eigendecomposition/eigenvalue maximization step for channel identification
Keywords :
channel coding; code division multiple access; delay estimation; eigenvalues and eigenfunctions; fading channels; interference suppression; multipath channels; optimisation; packet radio networks; packet switching; protocols; signal detection; spread spectrum communication; DS-CDMA; EM algorithm; channel identification; code delay acquisition; delay estimation; eigendecomposition; eigenvalue maximization; expectation maximization algorithm; flat-fading channel; frequency-selective channel; handshaking protocol; multipath coefficients; packet transmission; parallel interference cancellation; radiolocation; Application software; Delay estimation; Fading; Frequency; Gaussian noise; Interference cancellation; Multiaccess communication; Navigation; Protocols; Radiofrequency identification;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 2001. Proceedings. (ICASSP '01). 2001 IEEE International Conference on
Conference_Location :
Salt Lake City, UT
Print_ISBN :
0-7803-7041-4
DOI :
10.1109/ICASSP.2001.940441
