2G, 3G, 4G and Pre 5G Mobile Systems from A to Z
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商品描述GSM, GPRS, EDGE, CDMA, UMTS, HSPA intro, LTE, LTE-A, LTE-A Pro. Part I: Understanding GSM, GPRS and EDGEFundamentals of Cellular SystemGSM Network ArchitectureGSM Air InterfaceDigital Mobile ElementsGSM Network ProtocolsGPRS and EDGEPart II: Understanding CDMA and UMTSFundamentals of CDMAUMTS Evolution and Air InterfaceUMTS Network ArchitectureUMTS Protocol Stack & Physical layer processingUMTS Network ProtocolsPart III: Understanding Long Term EvolutionLTE Enabling TechnologiesLTE Network ArchitectureLTE Radio InterfaceLTE Protocol StackLTE Network ProtocolsLTE-A & LTE-A Pro A cellular network or mobile network is a communication network where the link to and from end nodes is wireless. The network is distributed over land areas called "cells", each served by at least one fixed-location transceiver (typically three cell sites or base transceiver stations). These base stations provide the cell with the network coverage which can be used for transmission of voice, data, and other types of content. A cell typically uses a different set of frequencies from neighboring cells, to avoid interference and provide guaranteed service quality within each cell.When joined together, these cells provide radio coverage over a wide geographic area. This enables numerous portable transceivers (e.g, mobile phones, tablets and laptops equipped with mobile broadband modems, pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations, even if some of the transceivers are moving through more than one cell during transmission. Cellular networks offer a number of desirable features: More capacity than a single large transmitter, since the same frequency can be used for multiple links as long as they are in different cellsMobile devices use less power than with a single transmitter or satellite since the cell towers are closerLarger coverage area than a single terrestrial transmitter, since additional cell towers can be added indefinitely and are not limited by the horizon