Prototype Experience for MIMO BLAST over Third Generation Wireless System
01 January 2003
In this paper, a multiple-input multiple-output (MIMO) extension for a third generation (3G) wireless system is described. The integration of MIMO concepts within the existing UMTS standard is explained. Bounds for optimum receiver performance are analytically derived and problems of a suboptimal RAKE-type received are pointed out. This analysis is followed by a description of an actual experimental receiver architecture and measurements are compared with an analysis of different MIMO detectors with respect to their performance and complexity. The prototype implementation of the system is realized on DSPs and FPGAs within a precommercial OneBTS base stattion. It uses four transmit and four receive antennas to achieve data rates of up to 1Mbps with a spreading factor of 32 and a chip rate of 3.84 MHz. The paper also presents a set of initial indoor over-the-air capacity and BER measurements.