Title :
On optimality of beamforming for multiple antenna systems with imperfect feedback
Author :
Jafar, Syed Ali ; Goldsmith, Andrea
Author_Institution :
Dept. of Electr. Eng., Stanford Univ., CA, USA
Abstract :
We determine a necessary and sufficient condition under which beamforming (scalar coding) achieves Shannon capacity in a narrowband point to point communication system employing multiple transmit antennas and a single receive antenna. We assume perfect channel state information at the receiver (CSIR) and either channel mean or channel covariance feedback from the receiver to the transmitter. We find that better feedback quality not only increases the system capacity but also reduces the required decoding complexity at the receiver
Keywords :
antenna arrays; antenna theory; array signal processing; decoding; encoding; fading channels; feedback; radio links; radio receivers; receiving antennas; transmitting antennas; Shannon capacity; beamforming; channel covariance feedback; channel mean feedback; decoding complexity; imperfect feedback; multiple antenna systems; multiple transmit antennas; narrowband point to point communication system; necessary and sufficient condition; perfect channel state information; receive antenna; receiver; scalar coding; system capacity; Antenna feeds; Array signal processing; Covariance matrix; Decoding; Eigenvalues and eigenfunctions; Receiving antennas; State feedback; Sufficient conditions; Transmitters; Transmitting antennas;
Conference_Titel :
Information Theory, 2001. Proceedings. 2001 IEEE International Symposium on
Conference_Location :
Washington, DC
Print_ISBN :
0-7803-7123-2
DOI :
10.1109/ISIT.2001.936184
