Characterization of vacant UHF TV channels for vehicular dynamic spectrum access

In this paper, we present quantitative and qualitative results obtained as a result of a TV spectrum measurement campaign. We used these measurements to characterize vacant TV channels a along major interstate highway (I-90) in the state of Massachusetts, USA. By characterizing the availability of vacant TV channels in the 470-806 MHz frequency range, we show the trends in the availability of vacant channels from a vehicular dynamic spectrum access perspective. We also describe the design constraints imposed on a point-to-multipoint communications based architecture in such a setting. Specifically, we described a general geo-location database approach to create a spectral map of available channels in a given geographical area. We presented the results obtained by applying such a technique in the state of MA over several locations on I-90. Furthermore, we presented a discussion on the implications of the non-contiguous channel availability in the TV spectrum on the design of a cognitive radio transceiver from the perspective of vehicular communications. In our future work, we will be presenting a comparative study of the channel availability in the above mentioned geographical area before and after the switch-over carried out on June 12, 2009.