In order to guarantee a continuous updating of the technology our group disposes, we have decided to offer our group and the municipal service in general a reception station with the weather images transmitted by the new satellite MSG1 or Meteosat 8. Through these data, we can do weather forecasts just by comparing the weather reports offered by the media and verify them through the analysis and the interpretation of the images received. This system has been installed after the weather forecast lessons taken by a big volunteers group and organized by the CAI section in Perugia . In fact, you can lay over images and simple software by using colour masks and filters. This procedure will also give you the opportunity to see in real time the rainfalls on a particular area thanks to an image having a resolution of 1 km (unlike the old Meteosat 7 which had a resolution of 2.5 km ). MSG1 or Meteosat 8 is the first European new generation geostationary satellite which replaces the old generation Meteosat satellite. The last one is Meteosat 7 located on the vertical of the Gulf of Guinea ( Africa ) and considered as the first European primary satellite. The new MSG1 satellite has just become operative, has taken the official name of Meteosat 8, has replaced Meteosat 7 and is classified as the first European primary satellite. The satellite launched on the 29 th of August 2002 placed itself first on a parking elliptical orbit. Then, its speed has been accelerated and after the two following steps the satellite has been placed on the definitive circular geostationary orbit, 36,000 km from the Earth. It was initially placed 10,5 degrees west latitude and about 0 degree longitude before replacing the last old generation geostationary satellite, the current Meteosat 7, at the beginning of 2004. On the 14 th August 2006 the position of MSG on the Equator was 0.9 degrees North Latitude and 8 degrees west longitude. At the beginning, the satellite should have transmitted the images taken by its 12 channels directly on the ground with the system LRIT and on the frequency of 1691 MHz for low-definition images, whereas for high definition images the frequency was 1695,15 MHz and the system used was HRIT. After the satellite launching, during its testing, there was a breakdown on the power amplifier SSPA which had to transmit the signal on the ground. After a first phase dedicated to the evaluation and solving of the problem, we came to the conclusion that the only way to transmit the signal on the ground was to use as relay (booster) bridge the satellite Hotbird 6 placed on an orbit next to Meteosat 8 and having quite big power amplifiers. However, this problem proved to be beneficial for people interested in this subject. In fact, now the data can be transmitted in DVB (digital video broadcasting), the system used for the transmission of satellite TV. This system requires fewer tools for data reception. At the beginning, because of the low power, the reception required a satellite antenna of at least 3 meters and a quite expensive receiver. Now, with a normal antenna of 90 cm and a card of satellite acquisition for personal computer, we can receive and decrypt the data without spending too much money. Very soon, the images of the screens of the received data and of the portable station created in our centre will be available.
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