Summary: | Many licensed and unlicensed frequency bands support heterogeneous wireless networks running different physical and link layer protocols. These networks ldquosharerdquo spectrum, but in an anarchic and arbitrary manner, resulting in poor performance for some networks and sub-optimal performance in aggregate. This problem is likely to be of importance in the US 700 MHz TV band, which is being explored for secondary use. This paper describes Metronome, a system that allows heterogeneous networks to coexist well. Metronome provides a flexible and expressive policy language that allows a network operator to specify constraints on receiver performance metrics such as throughput or loss rates. Metronome then configures each participating transmitter with appropriate channel, bandwidth, and transmission power settings automatically. Experiments from an outdoor vehicular platform for monitoring the TV band, and from an indoor heterogeneous network of 802.11, ZigBee and Bluetooth devices demonstrate the utility of Metronome's policy language. In a network of coexisting devices, we find that Metronome improves the throughputs of ZigBee and Bluetooth by more than 6 times and that of 802.11 by more than 15%.
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