TY - GEN
T1 - Adaptive modulation for MIMO multiplexing under average BER constraints and imperfect CSI
AU - Paris, José F.
AU - Goldsmith, Andrea J.
PY - 2006
Y1 - 2006
N2 - Adaptive modulation schemes for fading channels are usually required to fulfill certain long-term average BER targets. However, for simplicity and mathematical tractability, these schemes are often designed by fixing the short-term instantaneous BER to the target value. In this paper, the analysis and design of variable-rate variable-power QAM schemes with average BER constraints are tackled for MIMO multiplexing with imperfect CSI. The SISO system is considered as a special case of these more general results. Approximate closed-form policies are derived for continuous rate and power adaptation which are compared to the fully discrete policies. Our results indicate that MIMO multiplexing is much more sensitive to imperfect CSI than MIMO beamforming due to the self-interference that arises from channel coupling. In particular, if interference between eigenchannels is large, MIMO multiplexing should utilize only one of its eigenchannels, in which case all multiplexing gain is lost.
AB - Adaptive modulation schemes for fading channels are usually required to fulfill certain long-term average BER targets. However, for simplicity and mathematical tractability, these schemes are often designed by fixing the short-term instantaneous BER to the target value. In this paper, the analysis and design of variable-rate variable-power QAM schemes with average BER constraints are tackled for MIMO multiplexing with imperfect CSI. The SISO system is considered as a special case of these more general results. Approximate closed-form policies are derived for continuous rate and power adaptation which are compared to the fully discrete policies. Our results indicate that MIMO multiplexing is much more sensitive to imperfect CSI than MIMO beamforming due to the self-interference that arises from channel coupling. In particular, if interference between eigenchannels is large, MIMO multiplexing should utilize only one of its eigenchannels, in which case all multiplexing gain is lost.
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U2 - 10.1109/ICC.2006.254931
DO - 10.1109/ICC.2006.254931
M3 - Conference contribution
AN - SCOPUS:39349113962
SN - 1424403553
SN - 9781424403554
T3 - IEEE International Conference on Communications
SP - 1318
EP - 1325
BT - 2006 IEEE International Conference on Communications, ICC 2006
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2006 IEEE International Conference on Communications, ICC 2006
Y2 - 11 July 2006 through 15 July 2006
ER -