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Improvising Around A Disaster
The first of the U.S. Air Force’s AEHF (Advanced Extremely High Frequency) communications satellite was launched on August 14th. It achieved its initial orbit, but then it was discovered that its main maneuvering rocket, needed to get the six ton satellite into its permanent fixed, 36,000 kilometer, orbit, was not working. Efforts to get the main engine going failed. The engineers then went to work and found a way to use the lower thrust maneuvering rockets to still the AEHF bird into position. But the alternate method will be slower, and take about nine months. That’s a small price to pay for a satellite that is supposed to last 14 years, once you get it in the right position. AEHFs will replace the older MILSTAR birds, providing more abundant and reliable (jam-resistant) communications. Two more AEHFs are under construction, with one going up next year and another in 2012. Several more will be ordered if the first three (costing about $2.2 billion each) perform as expected. The cost of the first three includes development costs, so additional ones will cost less than half as much.
While the AEHF are mainly to facilitate communications between headquarters in the United States and troops abroad, they are also up there to deal with the huge increase in wireless devices the troops are using. For example, the number of military radios has nearly tripled, to over 900,000, in the last decade. There has also been a huge increase in data transmission capability (“bandwidth”) from 46 megabits (million bits) per second in late 2001, to nearly ten giga (billion) bits per second now. This is just for troops in CENTCOM (the Middle East and Afghanistan). That’s 200 times more data being pushed through three times as many “wireless devices” (radios). This doesn’t even count the many cell phones and laptops used by troops in the combat zone, which often use civilian bandwidth. But it hasn’t been enough.
The major consumer of all this new bandwidth is live video being generated by the increasing number of vidcams on the battlefield. These vids are being exchanged by the units cooperating in an operation. This huge growth in bandwidth began in the 1990s, when the U.S. armed forces moved to satellite communications in a big way. This made sense, especially where troops often have to set up shop in out of the way places and need a reliable way to keep in touch with nearby forces on land and sea, as well as bases and headquarters back in the United States. At the time of the 1991 Gulf War, there was enough satellite bandwidth in the Persian Gulf for about 1,300 simultaneous phone calls. Or, 12 megabits per second. But while the military has a lot more satellite capacity now (the exact amount is a secret), demand has increased even faster. UAV reconnaissance aircraft use enormous amounts of satellite capacity. The Global Hawk needed 500 megabits per second, and Predators about half as much. The major consumer of bandwidth is the live video.
UAVs have other sensors as well, as do aircraft. A voice radio connection only takes about 240 bytes per second, and each of the multiple channels needed to control the UAVs use about the same. But it adds up, especially since the military wants high resolution video. At the moment, the U.S. has far more demand for satellite communications than it can support. As a result, not all the Predator and Global Hawk UAVs in combat zones have sufficient bandwidth to send their video back to the United States. Data compression and using lower resolution is often necessary, or using satellite substitutes (aircraft carrying transponders) to send the video to local users. The substitutes are becoming more common, simply because there is neither the money, nor the time, to get sufficient satellites into orbit.
While the larger UAVs need satcomm to send video back to the United States, most of the bandwidth demand now is for local use. Tanks, helicopters and aircraft are all sending and receiving more vids, maps and data of all sorts. AEHF is needed to get essential material to higher headquarters as quickly as possible. The basic idea is to keep everyone connected, all the time. More radios, and other wireless devices are on the way, as well as more features any Internet user would recognize, all available while under fire. AEHF is an essential link in this data chain.
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TS2 Makes Sat Phones Available to Polish Ministry
TS2 has been awarded a contract for the supply of 150 satellite phones to the Polish Ministry of Foreign Affairs.
TS2 said the equipment is intended to secure communication in the event of emergency and the phones will be provided to Polish ambassadors and consuls across the world.
According to a release, diplomats frequently visit regions where no conventional mobile telecommunication system is available. Now they can use satellite connections ensuring global coverage and safety.
The satellite telephony system is aimed to secure mobile communication between the head office and overseas sites of the ministry in critical or emergency situations such as: evacuation of the site, natural disasters, breakdowns, local overload of terrestrial communication systems. They do not require terrestrial cell sites which are not installable in some areas, and which can be destroyed by natural disasters, sabotage or war actions.
Small could be the next big thing in satellite tech
It happened with our desktop computers shrinking into laptops and palm-sized gadgets and our mobile phones getting tinier. In the satellite industry too, ‘small’ could be the next big thing in the coming years.
A small satellite can equally suit communications, earth observation or surveillance, disaster monitoring or scientific experiments — the jobs that its bigger cousins do. It would weigh a few hundred kilos versus the 2-to-10-tonne giants that circle the earth today.
‘Smallsats’ cost less, weigh less, can be built fast and launched quickly in multiples and pack in just as much punch, according to Mr D.V.A. Raghav Murthy, ISRO’s Project Director for Small Satellites.
“They can achieve 90 per cent of what big satellites can at five per cent of the cost and do 17 per cent of their tasks at one per cent of the cost,” Mr Koteswara Rao, Director, Laboratory for Electro-Optics Systems at ISRO, corroborated.
A growing number of Governments, companies and user industries built around them are apparently warming up to their charms.
If India has had its IMS-1 and the upcoming IMS-2, both carrying the latest technologies in earth observation, Russia, the US and Israel are known to have small, short-life military spy satellites that can be quickly put into orbit.
Classed as nano or piko; micro (up to 100 kg) or mini (up to 500 kg), or the 10-cm ‘cubesats’, small sats cost under Rs 1 crore in India compared to Rs 200-300 crore for larger 2-tonne class satellites, Mr Murthy said at a session on small satellites at the Bengaluru Space Expo here.
Universities are eyeing smallsats as good educational tools for engineering students. ISRO, which recently launched StudSat, one such student satellite by Karnataka and Andhra Pradesh engineering students, has got inquiries from 22 institutions/universities and is trying to tell them to team up rather than each have a satellite.
IIT-Kanpur’s Jugnu and IIT-Bombay’s Pratham are in the pipeline, while Anna University’s Anusat was the first such Indian student satellite to go into orbit.
ISRO has launched many small satellites mainly for experimental purposes such as remote sensing, atmospheric studies, payload development, orbit control and recovery technology.
Dr Susmita Mohanty, Mumbai-based founder and CEO of space start-up Earth2Orbit India Pvt Ltd, said nano and small satellites for various purposes were showing a growth rate of at least 30 per cent a year led by the US and there would be 415 satellites in a near-earth orbit by 2014.
Earth2Orbit, which is an informal overseas marketing associate for ISRO’s earth imageries, also wants to bring in small satellites to be launched on the PSLV, which is emerging as a favourite in this band, she said. The smallsat launch business was pegged at $160 billion a year and the Indian workhorse launcher, she said, should capture at least 20 per cent of this business. Businesses are building around small sats. SSTL or Surrey Satellite Technology Ltd, the dedicated smallsat company now owned by Europe’s spacecraft major EADS Astrium, is building a small 200-kg spacecraft for Kazakhstan to support land mapping and resource management and planning. Launch majors such as Space X are eyeing these opportunities.