Field trial results for high-speed wireless indoor datacommunications

摘要

This paper reports on the development of a flexible 5-MBdnequalized M-QAM testbed for high-speed wireless data communications. Thenunit operates in real time and was field tested in typical indoornenvironments. A total of 3600 independent experiments were conductednusing the testbed where one of 4-, 16-, 64-QAM constellations werentransmitted, and the performance as a function of adaptive equalizationnand antenna selection diversity was studied. The experimental resultsnpresented here help put previous simulation and analytical results intonperspective and demonstrate some of the performance bounds associatednwith a practical implementation. The field trial results show that withnonly 10-mW of transmit power, reliable 10-Mbit/s data communication canntake place in between rooms with a coverage radius of 17 m, and betternthan 15% outage at an uncoded bit error rate (BER) of 10-3.nThe addition of two-branch antenna selection diversity to the systemnwould allow 10-Mbit/s transmission at better than 3% outage andn20-Mbit/s transmission at 10% outage in the same environment. Moreover,n30-Mbit/s data transmission is feasible when both the transmitter andnreceiver are located within the same room, albeit at higher outagenlevels. In general, the results demonstrate the tremendous impact thatnadaptive equalization can have on the achievable performance of indoornlinks. Average SNR was improved anywhere from 8 dB to 12 dB depending onnthe particular environment and data rate. The impact on the outagenperformance, however, was much more dramatic