Article Abstract:
With the proliferation of wireless devices, equitable apportionment and management of the radio spectrum has become more important. Military, commercial, private citizens, public safety, appliances: equipment in all these groups competes for space on the airwaves. Lower frequencies were the first to be commercialized, and are therefore the most widely used. They offer the best reception over the greatest distance with the least power expended in amplification. Advances in technology have made more of the high frequency wavelengths available, in the microwave part of the spectrum. But these presently require more repeating equipment to keep the signal going over longer distances or in areas of complex topography, like cities.
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Article Abstract:
Video CDs are gaining popularity in the world outside the US. Although the disks do not have the picture quality or the data-capacity of DVDs, they are about half the price and there is a more varied selection. Many of the video CDs made in Asian countries are pirated versions of US motion pictures. The Motioin Picture Association of America is watching the Asian market carefully and estimates that the association's members lose $3 billion annually from various forms of piracy.
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Article Abstract:
Internet Protocol telephony's popularity has grown as Internet use has grown. It is a less-expensive way to make phone calls worldwide. The technology is now approaching and international standard which will see the elimination of dropped calls and user-equipment incompatibility.
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