Title :
CDMA downlink channel estimation with aperiodic spreading
Author :
Weiss, Anthony J. ; Friedlander, Benjamin
Author_Institution :
Dept. of Electron. Syst., Tel Aviv Univ., Israel
Abstract :
Synchronous code-division multiple-access (CDMA) techniques possess intrinsic protection against co-channel interference due to the orthogonal spreading codes used. However, in the presence of multipath the signals lose their orthogonality properly leading to increased cross correlation. In these cases channel estimation may be needed in order to improve the detection of the desired symbols. We propose and compare several algorithms for channel estimation of a synchronous CDMA point to multipoint link (downlink) which uses aperiodic spreading waveforms. We compare by simulation and analysis a subspace approach, a pilot-aided approach, and a decision feedback approach.
Keywords :
code division multiple access; correlation methods; land mobile radio; multipath channels; parameter estimation; radio links; radiofrequency interference; signal detection; spread spectrum communication; aperiodic spreading waveforms; co-channel interference protection; code-division multiple-access; cross correlation; decision feedback approach; downlink channel estimation; mobile stations; multipath; multipoint link; orthogonal spreading codes; pilot-aided approach; simulation; subspace approach; symbol detection; synchronous CDMA; synchronous code-division multiple-access; Algorithm design and analysis; Analytical models; Channel estimation; Code division multiplexing; Communication standards; Downlink; Feedback; Interchannel interference; Multiaccess communication; Multicast algorithms;
Conference_Titel :
Signals, Systems & Computers, 1997. Conference Record of the Thirty-First Asilomar Conference on
Conference_Location :
Pacific Grove, CA, USA
Print_ISBN :
0-8186-8316-3
DOI :
10.1109/ACSSC.1997.680559
