| What
is a satellite broadcast?
A satellite broadcast (also called a satellite videoconference)
is an instructional session or meeting between people at different
locations that relies on satellite technology as the primary
communication link. During a broadcast, the "originator,"
or the location where the program is produced, transmits the
signal up to a receiving satellite orbiting the earth. This
is called "uplinking." The satellite in turn bounces
the signal back to earth where the signal is received by a
satellite dish, a process called "downlinking."
Program
originators purchase time on orbiting satellites on the open
market. To tune into a broadcast, the satellite receiver must
be programmed to receive the specific satellite coordinates
for a particular program. Satellite dishes have different
technical capacities and must be updated annually, so not
every site is capable of receiving every program.
Most
satellite broadcasts transmit sound and picture in one direction
only: from instructor to learner. To permit interaction between
instructor and learner, telephone and fax transmission is
often used between receiving and originating sites for questions
and comments. In some cases, programs are also broadcast live
over the Internet as well as by satellite. Many of these programs
are later archived so that Internet users can view them any
time they wish. See How
web-based learning works for more details.
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Learn about upcoming programs
Sources
Distance Learning Primer from CDC's Public Health Training
Network: www.cdc.gov/phtn/primer/htm
Helpful Guidance for Downloading CDC Programs: www.cdc.gov/phtn/guide/satellitecodes.htm
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