dailywireless.org » Routers in Space

Routers in Space

What do you get when you combine a high school library, an intercontinental ballistic missile, and a machine that makes sexy underwear? The answer is scheduled to blast off into space tonight.
– NPR, April 16, 2007

A Chinese navigation satellite was launched early Saturday, the second satellite in less than a week. The Beidou-2 satellite is said to be part of China’s planned Compass navigation system which will eventually consist of 5 GEO satellites and 30 MEO satellites. No timetable was given for the system’s completion.

The Chinese satellite navigation system is similar to, and may compete with, the United States’ GPS system, the Russian satellite navigation system GLONASS, and Galileo, the European satellite navigation system.

In other news, the Pentagon is funding an an $80 million Internet Protocol satellite. Dubbed IRIS for “Internet Routing In Space”, the satellite will be placed in geostationary orbit at 45 degrees West longitude with coverage of Europe, Africa and the Americas. SEAKR Engineering will manufacture the space-hardened router. The satellite, IS-14, is set for launch in the first quarter of 2009.

Traditionally, signals go directly down to ground-based earth stations. Transponders don’t link with each other, interconnect channels, or link to different satellites, explains Lloyd Wood, manager in the Global Defense, Space & Security division of Cisco.

Cisco and Intelsat hope to change all that. They plan to make IP routing in space cost/effective and will rent bandwidth to commercial users. The $80 million, three-transponder satellite will be built by Space Systems/Loral of Palo Alto, California. Most of the project’s cost will be borne by private investors corralled by California-based venture fund Concerto Advisors.

CHIPSat was the first satellite to be controlled using TCP/IP and FTP Internet protocols. Satellite control over the Internet using TCP/IP and FTP was demonstrated on the UoSat-12 microsat (Wikipedia), but CHIPSat was the first to implement the concept as the only means of satellite communication.

SpaceDev built the microsat for Berkeley’s Space Science Lab, under a NASA-funded $6.8 million fixed-price contract. The Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) satellite was designed for a one year mission to photograph interstellar background using all-sky spectroscopy.

SpaceDev develops micro and nano satellites, as well as hybrid rocket-based orbital Maneuvering and orbital Transfer Vehicles.

Berkeley’s Space Science Lab is involved in dozens of space research projects and has an advanced Microsat program. Many colleges and high schools are building their own CubeSat. Stanford’s CubeSat has the kit. CubeSats cost $5,000 to build and $30,000 to launch.

The CubeSat Program got a boost Tuesday from a Russian Dnepr rocket laden with 14 small international satellites.

Three P-POD deployment systems built at California Polytechnic State University housed seven miniature CubeSat payloads, including some utilizing tethers while others were orbited for Egypt and Saudi Arabia for reconnaissance. NPR has the story on Seattle-based Tethers Unlimited.

Satellite imagery can be produced by Earth observation satellites and Remote sensing satellites like Weather Satellites, Radar Satellites, InfraRed and even Lidar. Satellite radar imaging was among the most classified activities conducted by the US intelligence community. Now it’s pretty routine.

Imagery satellites complete about 15 revolutions around the Earth every 24 hours, with two daylight passes per day through the footprint of a typical Ground Receiving Station.

It takes 10-15 minutes to download satellite imagery from on-board memory. Live pictures are relayed to geosynchronous satellites like TDRSS.

But wouldn’t it be nice to get Internet maps — live. Day or night. In 3D.

Bill Grisham claims his global microwave imaging service could deliver hyperspectral content everywhere, all the time.

His concept, called MIRIAH (Microwave Interferometry Radiating Incrementally Accumulating Holography), would utilize an Interferometer satellite sensor, combining the best characteristics of SAR (Synthetic Aperture Radar) and Optical Satellites.

Grisham claims the technology could deliver all weather, day or night, imaging with extremely fine spatial resolution and extremely fine spectral resolution. MIRIAH throughput time might vary with the satellite population: from 12 hours for 3 satellites down to 30 minutes for 12 satellites.

But you’d need to ride piggyback on a handy satellite constellation (like GPS, Weather, Imaging or Phone satellites), plus a broadband inter-satellite link (like IRIS, perhaps). All sorts of Defense Satellites are available.

Astronomical interferometry might be the secret sauce, combining Submillimetre Astronomy with Aperture Synthesis. It’s used to combine signals from two or more platforms to obtain measurements with higher resolution. One picture can have a resolution nearly equivalent to the distance between the telescopes — which can be hundreds of miles in space. Like NASA’s Terrestrial Planet Finder.

Very Long Baseline Interferometry (VLBI) is a type of astronomical interferometry used in radio astronomy. A local atomic clock tags the imagery, then stores it for later analysis on magnetic tape or hard disk. Radio telescope arrays and more recently optical interferometer arrays like the Atacama Large Millimeter Array, COAST, NPOI and IOTA are most often performed at radio wavelengths.

The most sensitive VLBI array in the world is the European VLBI Network (EVN) where, 6 telescopes are now connected to JIVE with optical fibres at 1 Gigabit per second and the first astronomical experiments using this new technique (e-VLBI) have been successfully conducted. Four ground tracking stations are involved with the the Space Very Long Baseline Interferometry (SVLBI) program.

In December 2006, the NSF-NASA-DOE Astronomy and Astrophysics Advisory Committee (AAAC) established an ExoPlanet Task Force to advise NSF and NASA on the future of the ground-based and space-based search for and study of exo-planets, planetary systems, Earth-like planets and habitable environments around other stars.

The National Radio Astronomy Observatory has more on the Very Large Array Project.