Field Expelriments on Real-Time 1-Gbps High-Speed Packet Transmission in MIMO-OFDM Broadband Packet Radio Access

This paper presents field experimental results on real-time 1-Gbps packet transmission using antenna-dependent adaptive modulation and channel coding (AMC) with 4-by-4 MIMO multiplexing using maximum likelihood detection employing QR decomposition and the M-algorithm (QRM-MLD) with adaptive selection of the surviving symbol replica candidates (ASESS) in the downlink orthogonal frequency division multiplexing (OFDM) radio access. The field experiments, which are conducted at the average moving speed of 30 km/h, show that the real-time packet transmission of greater than 1 Gbps in a 100-MHz channel bandwidth (i.e., 10 bits/second/Hz) is achieved at the average received signal-to-interference plus background noise power ratio (SINR) of approximately 13.5 dB using 16QAM modulation and turbo coding with the coding rate of 8/9, The results also show that the antenna-dependent AMC is very beneficial to improve the measured throughput in a real propagation channel environments, where the average received power associated with each transmitted signal varies with the difference of greater than approximately 6 dB. Finally, we show that the measured throughput of greater than 1 Gbps is achieved employing antenna-dependent AMC at the probability of approximately 98% in a measurement course, where the maximum distance from the cell site was approximately 300 m with the respective transmitter and receiver antenna spacings of 1.5 m and 40 cm with the total transmission power of 10 W