Original Slides from Brough Turner Our G-enealogy Original Slides from Brough Turner Founder & CTO Ashtonbrooke.com broughturner@gmail.com http://blogs.broughturner.com Original slides: http://images.tmcnet.com/expo/west-09/presentations/4g3-01-turner-ashtonbrook.ppt

Our G-enealogy Brief history of cellular wireless telephony Radio technology: TDMA, CDMA, OFDMA Mobile core network architectures Demographics & market trends today 3.5G, WiMAX, LTE & 4G migration paths 2

Mobiles overtake fixed Source: ITU World ICT Indicators, June 2008 3

Mobile Generations G Summary Data Rates 1 2 2.5 3 3.5 4 Analog Typical 2.4 Kbps; max 22 Kbps 2 Digital – TDMA, CDMA 9.6 - 14.4 Kbps (circuit data) 2.5 GPRS – mux packets in voice timeslots 15 - 40 Kbps 3 Improved modulation, using CDMA variants 50 – 144 Kbps (1xRTT); 200 – 384 Kbps (UMTS); 500 Kbps – 2.4 Mbps (EVDO) 3.5 More modulation tweaks 2–14 Mbps (HSPA), then 28 Mbps & 42/84 Mbps future evolution 4 New modulation (OFDMA); Multi-path (MIMO); All IP LTE: potentially >100 Mbps with adequate spectrum (20 MHz)

First Mobile Radio Telephone, 1924 Courtesy of Rich Howard first two-way, voice-based radio telephone http://transition.fcc.gov/omd/history/radio/documents/short_history.pdf First two-way, voice-based radio telephone 5

Cellular Mobile Telephony Antenna diversity Cellular concept Bell Labs (1957 & 1960) Frequency reuse typically every 7 cells Handoff as caller moves Modified CO switch HLR, paging, handoffs 1 2 3 4 5 6 7 Antenna diversity, also known as space diversity, is any one of several wireless diversity schemes that uses two or more antennas to improve the quality and reliability of a wireless link. CO: central office Home Location Register (HLR) 6

First Generation (nearly all retired) Advanced Mobile Phone Service (AMPS) US trials 1978; deployed in Japan (’79) & US (’83) 800 MHz; two 20 MHz bands; TIA-553 Nordic Mobile Telephony (NMT) Sweden, Norway, Demark & Finland Launched 1981 450 MHz; later at 900 MHz (NMT900) Total Access Communications System (TACS) British design; similar to AMPS; deployed 1985 7

2nd Generation – digital systems Leverage technology to increase capacity Speech compression; digital signal processing Utilize/extend “Intelligent Network” concepts Improve fraud prevention; Add new services Wide diversity of 2G systems IS-54/ IS-136 Digital AMPS; PDC (Japan) DECT and PHS; iDEN IS-95 CDMA (cdmaOne) GSM 8

2G “CDMA” (cdmaOne) Code Division Multiple Access all users share same frequency band discussed in detail later as CDMA is basis for 3G Qualcomm demo in 1989 claimed improved capacity & simplified planning First deployment in Hong Kong late 1994 Major success in Korea (1M subs by 1996) Adopted by Verizon and Sprint in US Easy migration to 3G (same modulation) 9

GSM – Global System for Mobile Originally “Groupe Spécial Mobile ” joint European effort beginning 1982 Focus: seamless roaming all Europe Services launched 1991 time division multiple access (8 users per 200KHz) 900 MHz band; later 1800 MHz; then 850/1900 MHz GSM – dominant world standard today well defined interfaces; many competitors; lowest cost to deploy network effect took hold in late 1990s 10

Source: Wireless Intelligence / GSM Association GSM Dominant Today GSM+3GSM used by 88% of subscribers worldwide Asia leads with 42% of all mobile subscriptions AT&T and T-Mobile use GSM/3GSM in US today Source: Wireless Intelligence / GSM Association GSM Subscribers 11

GSM substantially enhanced Widely deployed  significant payback for enhancements HSCSD - high speed circuit-switched data GPRS - general packet radio service Synchronization between cells Minimize interference; help fix mobile’s location AMR vocoder – increase capacity (& fidelity) Frequency hopping (to overcome fading) Discontinuous transmission (more calls/ cell) Cell overlays with reuse partitioning 12

1G, 2G, 3G Multi-Access Technologies Courtesy of Petri Possi, UMTS World 4G and future wireless systems optimize a combination of frequency, time and coding e.g. OFDMA & SC-FDMA (discussed later) 13

2G & 3G – Code Division Multiple Access Spread spectrum modulation originally developed for the military resists jamming and many kinds of interference coded modulation hidden from those w/o the code All users share same (large) block of spectrum All 3G radio standards based on CDMA CDMA2000, W-CDMA and TD-SCDMA 14

Courtesy of Suresh Goyal & Rich Howard 15

The 3G Vision Universal global roaming Increased data rates Sought 1 standard (not 7), (but got 3: 3GSM, CDMA 2000 & TD-SCDMA) Increased data rates Multimedia (voice, data & video) Increased capacity (more spectrally efficient) Data-centric architecture (ATM at first, later IP) But deployment took much longer than expected No killer data app; new spectrum costly; telecom bubble burst; much of the vision was vendor-driven 16

3G Radio technology today CDMA 2000 – Multi Carrier CDMA Evolution of IS-95 CDMA; but now a dead end UMTS (W-CDMA, HSPA) – Direct Spread CDMA Defined by 3GPP Asynchronous CDMA TD-SCDMA – Time Division Synchronous CDMA Defined by Chinese Academy of Telecommunications Technology under the Ministry of Information Industry Paired spectrum bands Single spectral band with time division duplexing http://blog.naver.com/PostView.nhn?blogId=muyong1&logNo=40054698880 17

Why CDMA 2000 lost out Had better migration story from 2G to 3G Evolution from original Qualcomm CDMA (IS-95) cdmaOne operators didn’t need additional spectrum Higher data rates than UMTS, at least at first Couldn’t compete with GSM’s critical mass Last straw when Verizon Wireless selected 3GPP’s Long Term Evolution (LTE) for their 4G network Verizon selection 11/2007 Qualcomm abandons further development 11/2008 18

3GPP (3rd Generation Partnership Project) Japan USA Partnership of 6 regional standards groups, which translate 3GPP specifications to regional standards Controls evolution of GSM, 3GSM (UMTS, WCDMA, HSPA) & LTE

UMTS (3GSM) is market leader GSM evolution: W-CDMA, HSDPA, HSPA, +… leverages GSM’s dominant position Legally mandated in Europe and elsewhere Requires substantial new spectrum 5 MHz each way (symmetric) at a minimum Slow start (was behind CDMA 2000), but now the accepted leader Network effect built on GSM’s >80% market share Surely LTE will benefit in the same fashion… 20

TD-SCDMA (Time division synchronous CDMA) Chinese development IPR bargaining tool with West? Late to market, but big deployment plans Single spectral band unpaired spectrum; as little as 1.6 MHz; time division duplex (TDD) with high spectral efficiency Power amplifiers must be very linear relatively hard to meet specifications 21

China 3G Largest mobile market in world (630 M subs) Largest population in world (1.3 billion) Home-brew 3G standard: TD-SCDMA 3G licenses were delayed until TD-SCDMA worked 2008 trials: 10 cities, 15K BSs & 60K handsets 3G granted January 2009 China Mobile: TD-SCDMA China Unicom: 3GSM (UMTS) China Telecom: CDMA 2000 22

3G Subscribers (Q4 2011) http://kpcb.com/insights/2012-internet-trends 23

Diverse Mobile Wireless Spectrum 24

Wireless Migration

Wireless Subscribers in Korea 2012.2 2012.3 Changes +/- +/- % 방송통신위원회

4G OFDM →OFDMA MIMO LTE 3G WiMAX Wi-Fi 2G UMTS/HSPA Wireless capacity / throughput CDMA First cell phones GSM Increasing throughput and capacity AMPS 1970 1980 1990 2000 2010

ITU Framework Pervasive connectivity WLAN - WMAN - WWAN ITU – United Nations telecommunications standards organization Accepts detailed standards contributions from 3GPP, IEEE and other groups 3GPP – WWAN (wireless wide area network) IEEE 802.16 – WMAN (wireless metropolitan area network) IEEE 802.11 – WLAN (wireless local area network) 28

ITU-R Mobile Telecommunications IMT-2000 Global standard for third generation (3G) wireless Detailed specifications from 3GPP, 3GPP2, ETSI and others IMT-Advanced New communications framework: deployment ~2010 to 2015 Data rates to reach around 100 Mbps for high mobility and 1 Gbps for nomadic networks (i.e. WLANs) High mobility case via either or both evolved LTE & WiMAX 802.11ac and 802.11ad addressing the nomadic case 29

LTE highlights Sophisticated multiple access schemes DownLink: OFDMA with Cyclic Prefix (CP) UpLink: Single Carrier FDMA (SC-FDMA) with CP Adaptive modulation and coding QPSK, 16QAM, and 64QAM 1/3 coding rate, two 8-state constituent encoders, and a contention-free internal interleaver Advanced MIMO spatial multiplexing (2 or 4) x (2 or 4) downlink and uplink 30

4G Technology – OFDMA Orthogonal Frequency Division Multiple Access Supercedes CDMA used in all 3G variants OFDMA = Orthogonal Frequency Division Multiplexing (OFDM) plus statistical multiplexing Optimization of time, frequency & code multiplexing OFDM already deployed in 802.11a & 802.11g Took Wi-Fi from 11 Mbps to 54 Mbps & beyond 31

Orthogonal Frequency Division Multiplexing Many closely-spaced sub-carriers, chosen to be orthogonal, thus eliminating inter-carrier interference Varies bits per sub-carrier based on instantaneous received power 32

Statistical Multiplexing (in OFDMA) Dynamically allocate user data to sub-carriers based on instantaneous data rates and varying sub-carrier capacities Highly efficient use of spectrum Robust against fading, e.g. for mobile operation 33

FDMA vs. OFDMA OFDMA more frequency efficient Dynamically map traffic to frequencies based on their instantaneous throughput FDMA Channel Guard band

4G Technology - MIMO Multiple Input Multiple Output smart antenna technology Multiple paths improve link reliability and increase spectral efficiency (bps per Hz), range and directionality 35

Municipal Multipath Environment 36

SDMA = Smart Antenna Technologies Beamforming Use multiple-antennas to spatially shape the beam Spatial Multiplexing a.k.a. Collaborative MIMO Multiple streams transmitted Multi-antenna receivers separate the streams to achieve higher throughput On uplink, multiple single-antenna stations can transmit simultaneously Space-Time Codes Transmit diversity such as Alamouti code reduces fading 2x2 Collaborative MIMO give 2x peak data rate by transmitting two data streams 37

4G Technology – SC-FDMA Single carrier multiple access Used for LTE uplinks Being considered for 802.16m uplink Similar structure and performance to OFDMA Single carrier modulation with DFT-spread orthogonal frequency multiplexing and FD equalization Lower Peak to Average Power Ratio (PAPR) Improves cell-edge performance Transmission efficiency conserves battery life 38

Key Features of WiMAX and LTE OFDMA (Orthogonal Frequency Division Multiple Access) Users are allocated a slice in time and frequency Flexible, dynamic per user resource allocation Base station scheduler for uplink and downlink resource allocation Resource allocation information conveyed on a frame‐by frame basis Support for TDD (time division duplex) and FDD (frequency division duplex) DL UL FDD Paired channels TDD: single frequency channel for uplink and downlink

3G/4G Comparison Peak Data Rate (Mbps) Access time (msec) Downlink Uplink HSPA (today) 14 Mbps 2 Mbps 50-250 msec HSPA (Release 7) MIMO 2x2 28 Mbps 11.6 Mbps HSPA + (MIMO, 64QAM Downlink) 42 Mbps WiMAX Release 1.0 TDD (2:1 UL/DL ratio), 10 MHz channel 40 Mbps 10 Mbps 40 msec LTE (Release 8), 5+5 MHz channel 43.2 Mbps 21.6 Mbps 30 msec

WiMAX vs. LTE Commonalities Differences IP-based OFDMA and MIMO Similar data rates and channel widths Differences Carriers are able to set requirements for LTE through organizations like NGMN and LSTI, but cannot do this as easily at the IEEE-based 802.16 LTE backhaul is, at least partially, designed to support legacy services while WiMAX assumes greenfield deployments

Commercial Issues LTE Deployments likely slower than projected But Eventual migration path for GSM/3GSM, i.e. for > 80% share Will be lowest cost & dominant in 2020 WiMAX 2-3 year lead, likely maintained for years Dedicated spectrum in many countries But Likely < 15% share by 2020 & thus more costly

3G Partnership Project Defines migration GSM to UMTS/ 3GSM to LTE * Release Specs complete First deployed Major new features defined 98 1998 Last purely 2G GSM release 99 1Q 2000 2003 W-CDMA air interface 4 2Q 2001 2004 Softswitching IP in core network 5 1Q 2002 2006 HSDPA & IP Multimedia System (IMS) 6 4Q 2004 2007 HSUPA, MBMS, GAN, PoC & WLAN integration 7 4Q 2007 future HSPA+, Better latency & QoS for VoIP 8 4Q 2008 LTE, All-IP * * Rush job? W-CDMA – Wideband CDMA modulation HSxPA – High Speed (Download/Upload) Packet Access MBMS – Multimedia Broadcast Multicast Service GAN – Generic Access Network PoC – Push-to-talk over Cellular LTE – Long Term Evolution, a new air interface based on OFDM modulation 43

Core Network Architecture Two widely deployed architectures today 3GPP evolved from GSM-MAP Used by GSM & 3GSM operators (88% of subs globally) “Mobile Application Part” defines signaling for mobility, authentication, etc. 3GPP2 evolved from ANSI-41 MAP ANSI-41 used with AMPS, TDMA & CDMA 2000 GAIT (GSM ANSI Interoperability Team) allowed interoperation, i.e., roaming Evolving to common “all IP” vision based on 3GPP 44

Core Network Architecture Home Subscriber Server (HSS) performs AAA and subscriber database functionality, eliminating the need for a separate Radius server The Policy and Charging Rules Function (PCRF) server is an important element, taking care of the direct control of resources (quality of service) according to user profile Mobility Management Entity (MME) has a role similar to that of the Serving GPRS Support Node (SGSN) in the 3G packet core, except that it only carries the signalling path Serving GW (SGW) has inherited the SGSN's bearer role in 4G, transporting large amounts of traffic Packet Data Network Gateway (PDN GW) has replaced the Gateway GPRS Support Node (GGSN) in the 3G packet core, thus having the Network Access Server (NAS) role eNodeB serves in 4G instead of NodeB and Radio Network Controller (RNC) in 3G

Summary Brief history of cellular wireless telephony Radio technology: TDMA, CDMA, OFDMA Mobile core network architecture 46