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.SummaryAny individual 18 years of age or older who is not a repre-sentative of a foreign government is eligible to apply for aGMRS system license.There is a filing fee for new licensesand license renewals.For general information regarding thefee and filing requirements, contact the FCC s ConsumerCenter toll free at 1-888-225-5322.See alsoCitizens Band Radio ServiceFamily Radio ServiceLow-Power Radio ServiceGENERAL PACKET RADIO SERVICEGENERAL PACKET RADIO SERVICEMany carriers will take an interim step to third generation(3G), referred to as 2.5G, that uses the Internet Protocol (IP) toprovide fast access to data networks via General Packet RadioService (GPRS) technology.Compared to circuit-switched data(CSD), which operates at up to 14.4 kbps and high-speed cir-cuit-switched data (HSCSD), which operates at up to 43.2kbps, GPRS uses packet-switching technology to transmitGENERAL PACKET RADIO SERVICE 129short bursts of data over an IP-based network to deliver speedsof up to 144 kbps over an  always on wireless connection.True 3G networks based on enhanced data rates for GSMevolution (EDGE) technology deliver data at speeds of up to384 kbps.EDGE is a step beyond GPRS that will allow up tothree times higher throughput compared to GSM/GPRSusing the same bandwidth.Carriers in the United Stateshave been moving toward 3G for several years by overlayingvarious technologies onto their existing networks to enhancetheir data-handling capabilities.For carriers with TDMA-based networks, the first step tooffering true 3G services is to deploy Global Systems forMobile communications (GSM) and then GPRS.The GPRSenhancement to GSM can support peak network speeds ofwireless data transmissions between 64 and 170 kbps depend-ing on the various claims of hardware vendors.The newGSM/GPRS network does not replace existing TDMA net-works; carriers will continue supporting these networks longinto the future to service their voice customers.Eventually, allTDMAcustomers will be migrated to GSM/GPRS.Once the GSM/GPRS overlay is in place in a market, thecarriers can upgrade their networks with EDGE-compliantsoftware to boost data transmission rates to as much as 384kbps and begin the availability of true 3G services.Carriers whose wireless networks are based on CDMAwill take a different technology path to 3G, going throughCDMA2000, before eventually arriving at Wideband CodeDivision Multiple Access (W-CDMA).Both EDGE and W-CDMA offer a migration path to the global standardUniversal Mobile Telecommunications System (UMTS).Coverage for 2.5/3G services is still ramping up, despitethe impressive figures thrown out by individual carriers.The next step is for service providers to engage in moreroaming arrangements, which is a way to save costs, reducetime to market, and add value to attract more customers.The data speed of 2.5/3G services is determined by manyfactors, including the equipment and software in the wireless130 GENERAL PACKET RADIO SERVICEnetwork, the distance of the user from the nearest base sta-tion, and how fast the user may be moving.The claimedspeed of the service is rarely, if ever, achieved in the real-world operating environment.The pricing plans and price points differ by carrier, from asimple add-on to existing digital voice plans for a basic dataservice, to tiered pricing plans based on actual data usage.Depending on the applications, users can opt for 2.5/3Gcell phones with multimedia messaging capabilities.Alternatively, users with heavy messaging and file transferrequirements may opt for PC cards for notebooks and per-sonal digital assistants (PDAs).The choice of 2.5G platform depends on whether the car-rier has a TDMA- or CDMA-based network.Both technolo-gies are capable of eventual migration to full 3G and at ahigher level will be able to interoperate in compliance withthe global IMT-2000 initiative.Some service providers intend to support WirelessFidelity (Wi-Fi), as well as GPRS.Wi-Fi networks are basedon the IEEE 802.11b Standard for Ethernet, which operatesin the unlicensed 2.4-GHz band to provide a maximumstated speed of 11 Mbps.In actual operation, however, Wi-Fioffers between 5 and 6 Mbps [ Pobierz całość w formacie PDF ]