Equalized GMSK, equalized QPSK and OFDM, a comparative study for high-speed wireless indoor data communications

The proper choice of modulation and detection schemes to enable high-speed wireless indoor data communications has been the subject of extensive study. Of particular interest to ASIC designers is the complexity, cost and power dissipation of the analog and digital processing elements associated with such systems. This paper presents a side-by-side comparison of the three most popular system architectures for high-speed wireless data communications, namely equalized QPSK, equalized GMSK and OFDM. Their performance and minimum configuration at data rates up to 30 Mbps is measured and analyzed under a set of simulated indoor wireless channels with ensemble-average RMS delay spread /spl tau//sub RMS/ of 35 ns. The achievable channel capacity is proposed as a metric as well as outage and spectral efficiency. Finally, a single figure of merit is used to compare the three systems.