Title :
Multiple Access of MIMO OFDMA: TDMA, FDMA/TDMA, or SDMA/FDMA/TDMA
Author :
Liu, Guangyi ; Jiang, Feng ; Zhou, Bei ; Wang, Ying ; Zhang, Ping ; Cui, Hongyan
Author_Institution :
WTI Inst., Beijing Univ. of Posts & Telecommun.
Abstract :
Multiple input and multiple output (MIMO) can greatly enhance the performance of wireless system. However, the limited battery life and terminal size of the user equipment (UE) in a cellular system put a constraint on the performance enhancement by MIMO. Especially when the transmitter has more antenna than the receiver in downlink, the conventional MIMO schemes can only exploit partial multiplexing gain and diversity gain. For a multiuser system, multiuser diversity gain can be achieved by exploiting the independent frequency and spatial selective fading one another. In this paper, different multiuser multiple access schemes with greedy scheduling of MIMO OFDMA are investigated, e.g. TDMA, FDMA/TDMA and SDMA/FDMA/TDMA. For full spatial-frequency multiuser diversity gain and spatial multiplexing gain can be achieved, SDMA/FDMA/TDMA obtains highest spectrum efficiency. Its gain exceeds that of TDMA and FDMA/TDMA at least 80% and 40% respectively. The more antennas configured, the more gain can be observed from SDMA/FDMA/TDMA
Keywords :
MIMO communication; OFDM modulation; cellular radio; diversity reception; frequency division multiple access; radio receivers; radio transmitters; space division multiple access; time division multiple access; FDMA-TDMA; MIMO OFDMA; SDMA-FDMA-TDMA; TDMA; cellular system; frequency division multiple access; greedy scheduling; multiple input and multiple output system; multiuser diversity gain; partial multiplexing gain; receiver; space division multiple access; spatial selective fading; spectrum efficiency; time division multiple access; transmitter antenna; user equipment; wireless system; Batteries; Diversity methods; Downlink; Frequency division multiaccess; MIMO; Multiaccess communication; Receiving antennas; Time division multiple access; Transmitters; Transmitting antennas;
Conference_Titel :
Communications, Circuits and Systems Proceedings, 2006 International Conference on
Conference_Location :
Guilin
Print_ISBN :
0-7803-9584-0
Electronic_ISBN :
0-7803-9585-9
DOI :
10.1109/ICCCAS.2006.284895
