Technology - WebSat
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Web – Sat – Direct In present times there are many ways to get connected to the Internet. The cheapest one is so called dial-up, when the subscriber gets connected by means of his telephone link. In case he wants to avoid paying enormous amounts for the telephone account he must watch carefully the on-line time. Besides this version is too slow. Another way is for example a fixed link, whose monthly operation can cost about just below CZK 3000. But even for this price you don’t get much all you get for this money is just the 14,4 kbps link. In case of faster versions you pay for an unlimited access much more. The same case is with a wireless connection. On top of it, this connection is limited by direct visibility. But in complex built up areas and in places far away from civilisation we can’t satisfy this condition whatever we do. But still you would like to surf through the Internet and send e-mails. Let’s summarise once more again, what choice you are left with and let’s exclude subsequently individual possibilities until we arrive to the last one that while being slightly more expensive, it beats all other variants mentioned. But be ready for a surprise. The dial up is too slow, the ISDN you reject in principle, and the cable television is not installed in your place you haven’t got the direct visibility needed for a wireless link and a fixed link you simply don’t want. What would happen, if your company were to move to another corner of Europe? You wouldn’t definitely carry the cables along. Let me stop thrilling you to much – this ideal solution in the Czech republic is a quite unique possibility of an access to the Internet via a satellite, which is presented under the name Web-Sat Direct. Technical Specifications The antenna supplied is of an elliptical shape 100x80 cm that is in fact equivalent of the circular version of the diameter 84 cm. During a possible gust of wind it /resists, during a normal operation, up to the 80 km/ph wind stress. The limit value at which the antenna stability is still guaranteed is 200 km/ph. In our latitude and longitude such winds we never experience. But you can certainly go to sleep with a peace of mind, even when the weather outside is absolutely foul, that your valuable investment is save. Its transmitter power is 400 mW, whose supply is controlled from the board installed in a personal computer. As far as the connection cables are concerned, the satellite antenna can be placed up to 100 m distance. The Web-Sat (SIT) consist of the external parabolic antenna mentioned above of the diameter 80 cm, external receiver and transmitter unit, internal receiver and transmitter PC card, software and documentation. Associated supported operation systems are: MS Windows 95/98, Windows NT. In foreseeable future it has been counted still upon the Novell and Linux. On the receiver side the transfer speed reaches the unbelievable 350 kbps. Transmitting is quite slower – 16 kbps. In the near future an increase to 32 kbps is considered. System Description The Web–Sat Direct is the first device of new generation for continuous bi-directional connection on the Internet. The hub is connected to the spine heterogeneous Internet network by a light- guiding cable allowing fast and efficient connection. Data coming out of it are sent to user terminals by means of the DVB multiplexer with the speed of 4Mbps. (This speed can be increased in case of need). At the same time every terminal is equipped with a possibility of direct communication with the distributor, which is realised in a multiplex regime of the 16 kbps output. Besides the Web-Sat enables mutual interconnection of these devices by means of the satellite. This way two or more devices can be interconnected regardless their geographical dislocation. What are the implications for the Czechs who are interested? Only one thing and a very pleasant one: you can get connected without any difficulties from any place of our country…