AMSAT
The Radio Amateur Satellite Corporation
FACT SHEET


FACTS ABOUT THE AMSAT PHASE 3-D SATELLITE
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As currently designed, Phase 3-D will receive on the 15, 145, 436, 1270,
2400 and 5600 MHz Bands.  It will transmit on the 145, 436, 2400, 10,500
and 24,000 MHz bands.  Receive/transmit combinations will be
programmable from Earth through the onboard computer and a unique RF
matrix arrangement allowing one or more uplink receivers to be linked to
one or more downlink transmitters.  The satellite will weigh over 600 Kg
(1300 pounds) fully loaded with propellants at launch.  It will also be
about 2.3 meters (7.5 feet) in diameter and about 1 meter (3 feet) high.
With its solar panels extended, Phase 3-D's "wingspan" will be over 6
meters (20 feet).  Phase 3-D's elliptical orbit will vary from a maximum
height of 47,000 Km (29,000 miles) above the Earth to a low of some 4000
Km (2400 miles).  On-board antennas will offer gains in the 4 to 19 dBic
range which, because of the spacecraft's unique three-axis
stabilization, will always point Earthward.  When combined with on-board
power capability approaching 600 watts, these high-gain antennas will
produce effective downlink powers in the 10-20 Kilowatt range.

As Phase 3-D's transmitters and receivers will be programmable, this
concept will take the additional satellite mode designators that amateur
satellite operators have become used to (such as Modes A, B, and J),
virtually obsolete.  For example, on Phase 3-D, a Configuration "U/VS"
will be possible.  That is, amateurs will be able to uplink to the
satellite on U-Band (435 MHz) while the satellite transmits downlinks on
both V-Band (145 MHz) and S-Band (2400 MHz).  Simply looking  at the
frequency chart for Phase 3-D, it becomes apparent that a myriad of
different combinations (like Configurations "C/V", "UL/S" and "L/SC")
could all be supported!  Of course, the traditional Mode B, one of the
most popular modes on the current Phase 3 satellites, will become
Configuration "U/V" under this concept.  It is expected this frequency
pair will be one of the more active ones in the first years of Phase
3-D's lifetime.  However, as commercially available equipment for the
higher bands becomes more available and lower in cost, use of these
higher frequency bands is expected to increase.  When this happens,
Phase 3-D's powerful receiver and transmitter suites for these bands
will already be in orbit and available for use.

Other experiments planned for the new satellite include a Global
Positioning System (GPS) receiver that may also allow the satellite to
tell ground controllers where it's located at any time.  Two
Earthward-pointing digital cameras are also now slated to be included.


(Current as of April, 1998)


AMSAT is a registered trademark of the Radio Amateur Satellite Corporation.

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