INTELSAT VII: a flexible spacecraft for the 1990s and beyond
Article Abstract:
INTELSAT's purpose is to provide international communications, making connectivity a key requirement and an essential feature in all INTELSAT satellites. The INTELSAT VII series spacecrafts are projected to have a vital role in INTELSAT's global network beginning in 1992 and into the 21st century. The INTELSAT VII spacecraft is smaller and lighter than its predecessor because the orbital locations are the smaller ones over the Pacific Ocean and digital circuit multiplication equipment is available. The INTELSAT VII uses both the C-band spectrum and the Ku-band spectrum. Use of these bands should enable full exploitation of the distance-insensitive and universal access of the satellite medium. More EIRP and better linearity at both C-band and Ku-band is provided by the INTELSAT VII. There are seven main subsystems in the INTELSAT VII satellite bus: satellite control electronics, attitude determination and control subsystem, electrical power subsystem, propulsion subsystem, thermal control subsystem, structure subsystem, and mechanism subsystem.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1990
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Laser altimetry measurements from aircraft and spacecraft
Article Abstract:
The laser altimetry technique can measure the topography of planetary and lunar surfaces at high resolution. A short-pulse laser apparatus is mounted on an aircraft or spacecraft and sends pulses to and from the surface. The resulting signal is then sent to a receiving telescope. Q-switching is used to generate the pulses in the laser oscillator. The relatively new diode-pumped lasers incorporating gallium-arsenide semiconductors improve efficiency by an order of magnitude. A waveform digitizer processes the pulses received from the laser detectors and produces measurements of altitude and of the surface structure.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1989
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