An Analysis of MIMO Techniques for Mobile WiMAX Systems

Multiple input multiple output (MIMO) techniques ar e an essential part of of the IEEE 802.16e 2005 specifications, which form the basis of mobile WiMAX systems. In this chapter, we first discuss the basic tradeoffs betwe n diversity, interference cancellation and spatial multiplexing in MIMO systems, and we compar e optimum combining (OC), maximum-ratio combining (MRC) and interference canc ellation for different numbers of receive antennas. Then, we focus on the two mandato ry MIMO profiles in the IEEE specifications (Alamouti’s STC and the 2x2 spatial multiplexing scheme) and compare them when the first is combined with MRC at the receiver . The simulations made using the ITU pedestrian B channel indicates that Alamouti’s STC outperforms spatial multiplexing when the two schemes are operated at the same spectral e fficiency. We next give signal-to-noise ratio (SNR) thresholds for the operating regions of different modulation, coding and MIMO schemes included in WiMAX system specifications.

[1]  A. Annamalai,et al.  Performance evaluation of cellular mobile radio systems with successive cancellation of non-identically distributed co-channel interferers in a Rayleigh fading environment , 2003, 2003 IEEE Wireless Communications and Networking, 2003. WCNC 2003..

[2]  Jack M. Winters,et al.  Optimum Combining in Digital Mobile Radio with Cochannel Interference , 1984, IEEE Journal on Selected Areas in Communications.

[3]  Hikmet Sari,et al.  Orthogonal frequency-division multiple access and its application to CATV networks , 1998, Eur. Trans. Telecommun..

[4]  Ezio Biglieri,et al.  MIMO Link Adaptation in Mobile WiMAX Systems , 2007, 2007 IEEE Wireless Communications and Networking Conference.

[5]  R C Robertson,et al.  Digital Communications Over Fading Channels , 2004 .

[6]  Abbas Jamalipour,et al.  Wireless communications , 2005, GLOBECOM '05. IEEE Global Telecommunications Conference, 2005..

[7]  E. Biglieri,et al.  Diversity, interference cancellation and spatial multiplexing in MIMO mobile WiMAX systems , 2007, 2007 IEEE Mobile WiMAX Symposium.

[8]  Siavash M. Alamouti,et al.  A simple transmit diversity technique for wireless communications , 1998, IEEE J. Sel. Areas Commun..

[9]  Rohit U. Nabar,et al.  Introduction to Space-Time Wireless Communications , 2003 .

[10]  Robert W. Heath,et al.  Switching between diversity and multiplexing in MIMO systems , 2005, IEEE Transactions on Communications.