Feasibility Study of Uplink Transmission with 64 QAM Based on Results of MBWA System Field Trial

In this paper, we report on a mobile broadband wireless access (MBWA) system field trial with fast low-latency access with seamless handoff orthogonal frequency division multiplexing (FLASH-OFDM), which was carried out at Sendai city in Japan. This paper discusses the feasibility of uplink transmission with the maximum modulation level of 64 QAM, using the measured uplink throughput performances when the maximum modulation levels are quadrature phase shift keying (QPSK) and 16 quadrature amplitude modulation (QAM). The field trial results show that 64 QAM improves the uplink throughput performance in 30% of the field trial area. It is considered that the maximum modulation level of 64 QAM is feasible to provide a mobile broadband data communication service with a higher throughput in uplink as well as downlink.