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Specifically designed to offer simultaneous, connectivity over the Americas and Europe, Intelsat 805 allows delivery to both sides of the Atlantic with a single transponder. The simultaneous connectivity, combined with high C-band e.i.r.p. levels up to 40 dBW, make the Intelsat 805 the ideal choice to deliver simple and cost-effective solutions for any multimedia applications, such as Internet, tele-medecine, tele-education, compressed digital video, and other services supported by satellite news gathering (SNG) equipment and VSAT networks.
Embratel, Intelsat's Signatory for Brazil, has already leased several transponders on the Intelsat 805 satellite, many of which will be primarily dedicated to carry internet traffic. Because of its high power, Intelsat 805 has the ability to reach operators with antennas as small as 1.8 meters, allowing for instant Internet backbone connectivity at lower infrastructure costs while bypassing terrestrial network congestion. [A satellite that is well-known for Internet services is Orion 1--even this so-called newsletter is sent via Orion 1.]
The spacecraft is expected to commence commercial service in the middle of July 1998 upon completion of orbital manoeuvres and in-orbit testing.
Specifications
Intelsat 805 is a Lockheed Martin Series 7000, the sixth and final satellite in a series of spacecraft delivered to Intelsat by Lockheed Martin Telecommunications. Intelsat 805 offers a total of 31 transponders, 28 at C-band and three at Ku-band, for optimised coverage for landmass areas for Intelsat's voice/data and video services. The entire Intelsat VIII/VIII-A series of six satellites was delivered to Intelsat within a fifteen-month time period.
The development of the global navigation satellite system (GNSS) will be carried out in two main stages. GNSS-1 will be the first-generation system, based on signals received from the existing American GPS and Russian Glonass constellations and civil augmentation systems using space based, ground based and mobile autonomous based technology. The European space based augmentation system is known as EGNOS (European Geostationary Navigation Overlay Service), a set of navigation payloads on-board geostationary satellites, continuously monitored by ground stations both within and outside Europe. The system, to be completed by 2002, will be developed by ESA.
GNSS-2, the second-generation system, will provide services to civil users and will be under civil operation and control by 2010. A decision on how to proceed with GNSS-2 will be taken within Europe by mid-1999.
The new satellite, designated Brasilsat B-4, is a wide-body version of the HS 376 model satellite and matches the capabilities of Embratel's three other spacecraft. Brasilsat B-4 will contain 28 C-band transponders to deliver voice, data, corporate networks and television service for a period of more than 12 years.
Brasilsat B-4 is scheduled for launch in late 1999. Embratel will make launch-vehicle arrangements separately.
Embratel: http://www.embratel.net.br/
First of all: I'm not opposed to Internet via satellite, on the contrary. It might be be a chance for people living in countries ruled by net-nanny governments to get (more or less) uncensored access. For example, there's a remote chance that Internet access providers in Germany may be obliged to set up compulsory proxy servers to filter out unwanted content, which by the way is exactly how China tries to limit Internet access.
Anyway, the protagonists of individual Internet access via satellite usually emphasise the available bandwidth and speed of the service. Users have encountered problems, though--probably not just because of the current implementation of the TCP/IP stack under Windows 95/98 but because any Internet connection can only be as fast as its weakest link.
FTP software said its new software, developed under contract with Intelsat, will increase throughput performance significantly for Internet browsing and file transfers over Intelsat satellite links as well as through high-speed terrestrial connections.
The new FTP Software release contains Internet Engineering Task Force-approved options which are specifically designed to improve Internet performance and include: facilitating a larger window size (which increases the maximum data throughput); providing fast recovery and fast retransmit (which together improve the way TCP recovers from loss of packets owing to errors and congestion); and providing selective acknowledgments (which allow for the acknowledgment of packets received out of sequence).
Said Conny Kullman, Intelsat's Vice President for Operations & Engineering: "This is another step toward removing customers' false perceptions about Internet protocols not being compatible with geostationary satellites. In this regard, we see the Intelsat system playing a major role in making the World Wide Web truly world-wide."
The software, which is incorporated in FTP Software's TCP/IP Stack Version 4.0, is also available for a free 30- day trial during a one-year promotional period.
FTP Software: http://www.ftp.com/
The HGS press release said the satellite had an inclination of a few degrees. The question is, of course, "exactly how many?"
Here are the latest Keplerian elements from NORAD for the spacecraft they still call Asiasat 3:
1 25126U 97086A 98169.33639973 .00000115
00000-0 10000-4 0 1008
2 25126 8.7156 302.0321
0027393 336.0867 317.1918 1.00403510 2593
If you read this in HTML, you will see the inclination bold and underlined: it's over 8.7 degrees. This is quite a lot and probably too much for any commercial application. However, please note the satellite is not in its final orbit; it's not even really geostationary. From the data above, which reflect the satellite's orbit yesterday at around 0800 UTC, I calculated a drift of .5 degrees eastward per day. (Current position is at around 156 degrees West.)
As a matter of fact, the inclination of geostationary satellites usually is a consequence of reduced stationkeeping. As the lunar flyby manoeuvres cost some fuel (I don't know how much, they didn't tell) the satellite will have to be kept in an inclined orbit, but I guess the inclination will be significantly less than 8.7 degrees when (and if) it will be put into service. There is no use whatsoever in keeping HGS-1 in a usable orbit before any customer is found.
The second question is also very interesting: Could HGS-1 have suffered any damages from its two trips to the moon--you never know what's out there in space? Well of course, there's always the chance of being hit by a micro-meteorite or something like that, but I think that in general the geostationary orbit is a much more hazardous area, and so was the 'wrong' orbit in which the satellite ended up after being launched.
The above is just my personal opinion, though, and please keep in mind I'm not an expert at all.
Q: What's the difference between
unlawful and illegal?
A: Unlawful means against the law, and
illegal is an ill bird.
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