JOURNAL OF NETWORKS (JNW)
ISSN : 1796-2056
Volume : 3    Issue : 7    Date : July 2008

Datacasting In The Mobile Environment
Kent Chamberlin, Benjamin McMahon, and Scott Valcourt
Page(s): 49-55
Full Text:
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Abstract
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 were installed in 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 network infrastructure and equipment used.
Although datacasting provides only a downlink channel, it can be interfaced with other channels so
as to form a twoway link. In the work reported here, datacasting was coupled with a broadband
cellular channel to successfully provide a two-way data channel.
It is important to note that this paper addresses the use of conventional datacasting, which is
particularly sensitive to multipath interference. For example, conventional datacast reception is not
possible when the receiver is in motion. Newer forms of datacasting that are less susceptible to
multipath are currently under development and should be on the market in the near future.
Consequently, some of the limitations of conventional datacasting reported here may not be factors
with the newer versions of datacasting.

Index Terms
Datacasting, Mobile, Antenna, UHF, Rain Effects, 8VSB modulation