The Digital Fact Book - Quantel

WidescreenA TV picture that has an aspect ratio wider than the ‘normal’ 4:3 – usually 16:9 – while stillusing the normal 525/60 or 625/50 or SD video. 16: 9 is also the aspect ratio used forHDTV. There is an intermediate scheme using 14:9 which is found to be more acceptablefor those still using 4:3 displays. Widescreen is used on some analog transmissions as wellas many digital transmissions. The mixture of 4:3 and 16:9 programming and screens hasgreatly complicated the issue of safe areas.See also: Safe AreaWiMAXWorldwide Interoperability for Microwave Access (IEEE 802-16 and ETSI HiperMAN),is a standards-based technology enabling the delivery of last-mile wireless broadbandaccess as an alternative to cable and DSL. Unlike Wi-Fi, this provides symmetrical bandwidth(equal upload and download speeds) over many kilometers with stronger encryption(3DES or AES). It connects between network endpoints without the need for line-of-sightof the base station for fixed, nomadic, portable and mobile wireless broadband. Typical cellradius is 3-10 km, delivering capacity up to 40 Mb/s per channel, for fixed and portableaccess – enough bandwidth to support hundreds of businesses and thousands of homes.Mobile networks are expected to provide up to 15 Mb/s capacity within 3 km cell radius.WiMAX technology already has been incorporated in some notebook computers and PDAs,allowing urban areas and cities to become MetroZones for portable outdoor broadbandwireless access.See also: OFDMAWebsite: www.wimaxforum.orgW179