Praise for Fundamentals of WiMAX

1.7 Technical Challenges for Broadband Wireless 311.7.8 Summary of Technical ChallengesTable 1.5 summarizes the various technical challenges associated with meeting the servicerequirements for broadband wireless, along with potential solutions. Many of the solutions listedare described in more detail in Part II of the book.Table 1.5 Summary of Technical Design Challenges to Broadband WirelessServiceRequirementsNon-line-of-sightcoverageHigh data rate andcapacityQuality of serviceMobilityPortabilitySecurityTechnical ChallengeMitigation of multipath fading andinterferenceAchieving high spectral efficiencyOvercoming intersymbol interferenceInterference mitigationSupporting voice, data, video, etc. ona single access networkRadio resource managementEnd-to-end quality of serviceAbility to be reached regardless oflocationSession continuity while moving fromthe coverage area of one base stationto anotherSession continuity across diverse networksReduce battery power consumption onportable subscriber terminalsProtect privacy and integrity of user dataPrevent unauthorized access to networkPotential SolutionDiversity, channel coding, etc.Cellular architecture, adaptive modulationand coding, spatial multiplexing, etc.OFDM, equalization, etc.Adaptive antennas, sectorization, dynamicchannel allocation, CDMA, etc.Complex MAC layerEfficient scheduling algorithmsIP QoS: DiffServ, IntServ, MPLS, etc.Roaming database, location update, pagingSeamless handoverIP-based mobility: mobile IPPower-efficient modulation; sleep, idlemodes and fast switching between modes;low-power circuit; efficient signal-processingalgorithmsEncryptionAuthentication and access controlLow costProvide efficient and reliable communicationusing IP architecture and protocolsAdaptation of IP-based protocols for wireless;adapt layer 2 protocols for IP