摘要

Spectrum measurement for seven days of E-GSM, GSM900 and DCS1800 bands based on cognitive radio is conducted. By statistical analysis, results show that the utilizations of different services are not the same, and it has significant difference between the occupancies of uplink and downlink channels. The occupancy of uplink channels is relatively lower than that of downlink, reflecting the phenomenon of being more vacant while people are resting at night, and busier while working. Meanwhile, the probability distributions of channel occupancy and signal level are analyzed. Besides, channel occupancy state can be modeled as a two-state discrete-time Markov chain, and the statistical residence time distributions of channel staying vacant and occupied are simulated, which yield the modified form of exponential distribution. Finally, the effects of cognitive radio with different performance on spectrum utilization are simulated.

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