TY - GEN
T1 - Single-user MIMO vs. multiuser MIMO in the broadcast channel with CSIT constraints
AU - Zhang, Jun
AU - Andrews, Jeffrey G.
AU - Heath, Robert W.
PY - 2008/12/1
Y1 - 2008/12/1
N2 - This paper considers fundamental limits on adaptive multiple-input multiple-output (MIMO) transmission with imperfect channel state information at the transmitter (CSIT). First, the achievable ergodic rates are derived for both single-user and multi-user MIMO systems with different CSIT assumptions, which shows that single-user MIMO is robust to imperfect CSIT while multiuser MIMO loses spatial multiplexing gain in proportion to delay and inverse with channel quantization codebook size. A single-user/multiuser mode switching rule is then proposed based on the average SNR, the amount of delay, and the quantization codebook size. The operating regions for single-user and multiuser modes are determined, which can be used to select the preferred mode. It is shown that the multiuser mode should not be activated when the delay is large or the codebook size is small.
AB - This paper considers fundamental limits on adaptive multiple-input multiple-output (MIMO) transmission with imperfect channel state information at the transmitter (CSIT). First, the achievable ergodic rates are derived for both single-user and multi-user MIMO systems with different CSIT assumptions, which shows that single-user MIMO is robust to imperfect CSIT while multiuser MIMO loses spatial multiplexing gain in proportion to delay and inverse with channel quantization codebook size. A single-user/multiuser mode switching rule is then proposed based on the average SNR, the amount of delay, and the quantization codebook size. The operating regions for single-user and multiuser modes are determined, which can be used to select the preferred mode. It is shown that the multiuser mode should not be activated when the delay is large or the codebook size is small.
UR - http://www.scopus.com/inward/record.url?scp=64549116322&partnerID=8YFLogxK
U2 - 10.1109/ALLERTON.2008.4797572
DO - 10.1109/ALLERTON.2008.4797572
M3 - Conference article published in proceeding or book
AN - SCOPUS:64549116322
SN - 9781424429264
T3 - 46th Annual Allerton Conference on Communication, Control, and Computing
SP - 309
EP - 314
BT - 46th Annual Allerton Conference on Communication, Control, and Computing
T2 - 46th Annual Allerton Conference on Communication, Control, and Computing
Y2 - 24 September 2008 through 26 September 2008
ER -