Evaluation of Datacasting in the Mobile Environment

Datacasting employs the excess bandwidth from digital television signals for use in one-way data transmission, and it is being used successfully for high-speed downloads at fixed locations. There is considerable interest in extending datacast usage to mobile users, although there are reception challenges in the mobile environment that can significantly impact system performance. To explore the feasibility of using datacasting in this environment, datacasting receivers and data logging equipment have been installed in 10 emergency vehicles to record performance characteristics over a wide range of operational conditions. Summary conclusions from that study are described in this paper along with details about the equipment used to make the test and the environmental factors that were found to have the greatest impact on system performance. The use of the low-speed (9600 baud) VHF, emergency-band data channel in conjunction with the datacast channel to provide two- way data transmission is also evaluated and discussed for the mobile environment.