Slide 1TopicsCellphones1G2G2.5G and 2.75G3G3G - UMTS3G – CDMA20004GOFDMAMIMOLTEWiMAXNot technically 4GHSDPA, HSUPA, HSPA+So what satisfies IMT-Advanced?Social/Ethical considerationsSourcesFourth Generation (4G)Wireless SystemsJeremy MayeresTopicsCellphones1G2G3G4G/IMT-AdvancedLTEWiMAX4G TodayFuture of 4GSocial/Ethical considerationsCellphonesRadio telephony existed long before cell phones became popular1947 – Ring and Young working at Bell Labs develop idea of using “hexagonal cells”1973 – First cell phone call – Martin Cooper of Motorola1GAnalog systemAdvanced Mobile Phone System (AMPS) in the USFrequency Division Multiple Access (FDMA) – Different frequency for each conversationIssuesListen in with a scannerSpoofing2GDigitalTime Division Multiple Access (TDMA)GSM (Global System for Mobile Communications)D-AMPS (Digital AMPS, superseded by GSM)iDEN (Integrated Digital Enchanced Network)Code Division Multiple Access (CDMA)IS-95/cdmaOne2.5G and 2.75G2G with always-on dataGeneral Packet Radio Service (GPRS)2.5G for GSMMaxed at about 115 Kbps1xRTT2.5G for CDMAMaxed at about 153 KbpsEnhanced Data rates for GSM Evolution (EDGE)2.75GSpeeds up to 1 Mbps3GInternational Telecommunications Union (ITU) International Mobile Telecommunications-2000 (IMT-2000)Requires minimum speed of 200 Kbps3rd Generation Partnership Project (3GPP) – 3G Upgrade for GSM3GPP2 – 3G Upgrade for CDMA3G - UMTSUniversal Mobile Telecommunications System (UMTS) by 3GPPUses W-CDMA (Wideband CDMA)Handles voice and dataData speeds about 384 Kbps (R99) to 2 MbpsMore on this later…3G – CDMA20003GPP2 GroupBackwards compatible with cdmaOne1xEV-DO (or just EV-DO) Evolution-Data OptimizedRev. 0: Max speed of about 2.4 Mbps download, 153 Kbps uploadRev. A: Max speed of about 3.1 Mbps download, 1.8 Mbps upload4GIMT-Advanced by ITUGlobal useHigh-quality servicesUser-friendlyHigh speeds: 1 Gbps stationary, 100 Mbps mobileSpectrum efficiencyIP packet-switched networkLTE (Long Term Evolution)IEEE 802.16 “WiMAX” (Worldwide Interoperability for Microwave Access)OFDMAOrthogonal Frequency-Division Multiple AccessSplit channel into sub-carriersUser is assigned multiple sub-carriers:Closer to base gets more sub-carriers (more bandwidth)Further away, get less sub-carriers, but use more powerOFDM also used in 802.11a/g/nMIMOMultiple In – Multiple OutDiversityAvoid fading due to multipath interference, shadowsSpatial MultiplexingUse multiple channels to get higher data ratesLTE3GPPVerizon, MetroPCS, AT&T, and SprintUpgrades UMTSUses MIMO, OFDMAIP-based700 MHz BandSpeed: 100 Mbps download, 50 Mbps uploadWiMAXIEEE 802.16e-2005Scalable OFDMA (SOFDMA) – Scales the Fast Fourier Transform (FFT) size for different bandwidthsPrimarily uses 2.5 GHz band in the US (Clear/Sprint)Use as backhaulCloser to WiFiSpeeds up to 40 MbpsNot technically 4GWiMAX and LTE in today’s networks do not meet the IMT-Advanced criteriaEvery major wireless 4G network fails to meet IMT-Advanced criteriaITU accepts WiMAX and LTE as “Pre-4G”Can also be called 3.9GNetworks still calling it 4GHSDPA, HSUPA, HSPA+“High Speed Packet Access,” part of 3GPPD – Downlink, U – UplinkHSDPA – 7.2 Mbps, HSUPA – 1.9 MbpsHSPA+ (Evolved HSPA)84 Mbps download, 22 Mbps uploadMIMOAll-IP OptionStill part of 3G, UMTST-Mobile/AT&T calling it 4GSo what satisfies IMT-Advanced?LTE-Advanced (3GPP) and WirelessMAN-Advanced (IEEE 802.16m)Not yet availableWill satisfy the 1 Gbps download speed requirementWhat will this be called?Social/Ethical considerationsIs 4G just a marketing term?Bringing broadband to everyoneWireless capacity and Net NeutralitySourcesIMT-Advanced - Objective and Challenges by K. Jay Miyahara An Overview of Next-Generation Mobile WiMAX Technology by Sassan AhmadiOn the Way towards Fourth-Generation Mobile: 3GPP LTE and LTE-Advanced by David Martin-Sacristian, et al.History of Mobile Telephones (Wikipedia and related
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