EURASIP Journal on Applied Signal Processing 
Volume 2006 (2006), Article ID 45401, 10 pages
doi:10.1155/ASP/2006/45401

A High-Speed Four-Transmitter Four-Receiver MIMO OFDM Testbed: Experimental Results and Analyses

Weidong Xiang,1 Paul Richardson,1 Brett Walkenhorst,2 Xudong Wang,3 and Thomas Pratt2

 1ECE Department, University of Michigan-Dearborn, 126 ELB, 4901 Evergreen Rd., Dearborn 48128, MI, USA
2Communications and Networking Division, Information Technology and Telecommunications Laboratory, Georgia Tech Research Institute, Atlanta 30332-0832, GA, USA
3Kiyon Company, 4225 Executive Square, Suite 290, La Jolla 92037, CA, USA
Received 30 November 2004; Revised 1 September 2005; Accepted 1 September 2005

Abstract

By adopting multiple-input multiple-output (MIMO) and orthogonal frequency-division multiplexing (OFDM) technologies, indoor wireless systems could reach data rates up to several hundreds of Mbits/s and achieve spectral efficiencies of several tens of bits/Hz/s, which are unattainable for conventional single-input single-output systems. The enhancements of data rate and spectral efficiency come from the fact that MIMO and OFDM schemes are indeed parallel transmission technologies in the space and frequency domains, respectively. To validate the functionality and feasibility of MIMO and OFDM technologies, we set up a four-transmitter four-receiver OFDM testbed in a typical indoor environment, which achieves a peak data rate of 525 Mbits/s and a spectral efficiency of 19.2 bits/Hz/s. The performances including MIMO channel characteristics, bit-error rate against signal-to-noise ratio curves, the impairments of carrier frequency offset and channel estimation inaccuracy, and an asymmetric MIMO scheme are reported and analyzed in this paper.