AMSAT-NA Microsats
AMSAT-NA Microsat.
Microsats - what are they?
Microsat is the name for AMSAT North America's small spacecraft
design. Meant as a multi-mission
platform, the 22cm x 22cm x 22cm cube, weighing about 10kg,
usually carries a complement of two
transmitters, four receivers, battery and power management, a V40
or better class CPU with eight or
more megabytes of memory, and an additional experiment module.
The experiment module has been
used for S-band transmitters, high speed modems, CCD imagers,
meteor sounders, and other items.
The Microsats are meant to be very simple spacecraft to operate,
with passive attitude control and
autonomous power management.
January 1995 starts the fifth year of operation for the original
four Microsats. The first four were
- PACSAT - AO-16
- DOVE - DO-17
- WEBERSAT - WO-18
- LUSAT - LO-19
Since that time, two other Microsat derived satellites have been
placed in orbit,
- ITAMSAT - AO-26
- EYESAT - AO-27
All of these spacecraft are still functioning well in orbit.
Another Microsat is awaiting launch, UNAMSAT-1, built by the
Universidad Nacional Autonom de Mexico, in Mexico City.
Photos
An index to several microsat photographs from the microsat construction and
launch is available, one with thumbnail images, and one with
text only.
Protocols
The Microsats share a common operating system and much of their
software with another small satellite bus, the UoSATs built by Surrey Satellite Technology Ltd. (SSTL) . The operating
system, developed by Harold Price, NK6K,
supports the various spacecraft computer designs (80c188, 80c186,
80386ex, V40, V53) and provides a common application support
platform. The file transfer protocols
, designed by Jeff Ward, K8KA/G0SUL of SSTL, and NK6K, and
implemented by K8KA allow users of AO-16, LO-19, UO-22, KO-23,
KO-25, IO-26, and UNAMSAT-1 to use standardized ground software.
UoSAT-14/HealthSat-1 and PoSAT, two commercial UoSATS, also use
these protocols, and have been on amateur frequencies in the
past. Five amateur spacecraft that are under development will
also use these protocols. This represents the largest number of
software compatible amateur spacecraft ever.
The file transfer protocol definition documents are available.
People
Many people are involved in any spacecraft project,
the Microsat Project was no exception.
Spacecraft Descriptions
Short descriptions of
each of the spacecraft mentioned on this page
are now available.
Last modified: January 19, 1995
Harold Price,
NK6K, hprice@bektek.com