Title :
Application of unitary transforms to quasi-closed-loop transmit diversity systems
Author :
Mandyam, Giridhar D.
Author_Institution :
Nokia Res. Center, Irving, TX, USA
fDate :
Oct. 29 2000-Nov. 1 2000
Abstract :
Previous work in mobile wireless communications systems has centered on the use of closed-loop transmit diversity to increase performance in fading channels. Closed-loop transmit diversity methods, which employ feedback of optimal weighting vectors so as to pre-weight transmitted symbols from multiple antennas, suffer from two problems: (1) degradation at high mobile velocities due to limited-rate feedback, and (2) increasing feedback information rate with increasing number of transmit antennas. A method of closed-loop transmit diversity which addresses both of the problems listed above is presented based on the use of unitary transformations for transmitter diversity.
Keywords :
closed loop systems; diversity reception; fading channels; feedback; land mobile radio; optimisation; radio transmitters; transforms; fading channels; feedback information rate; high mobile velocities; limited-rate feedback; mobile wireless communications systems; multiple antennas; optimal weighting vectors feedback; quasi-closed-loop transmit diversity systems; space-time block code; transmit antennas; transmitter diversity; unitary transforms; Antenna feeds; Degradation; Diversity methods; Fading; Feedback; Information rates; Mobile antennas; Transmitters; Transmitting antennas; Wireless communication;
Conference_Titel :
Signals, Systems and Computers, 2000. Conference Record of the Thirty-Fourth Asilomar Conference on
Conference_Location :
Pacific Grove, CA, USA
Print_ISBN :
0-7803-6514-3
DOI :
10.1109/ACSSC.2000.910924
