1. ECE 4730: Lecture #27 1  Advanced Mobile Phone Service (AMPS) – 1G Analog FM  IS-136 (aka USDC, IS-54) – 2G Digital TDMA  Global System for Mobile (GSM) – 2G Digital TDMA  European  IS-95 CDMA – 2G Digital CDMA  U.S. / Qualcomm  2.5G Standards – TDMA/CDMA  CDMA2000 – 3G U.S./Qualcomm  W-CDMA – 3G Europe Cellular Standards

2. ECE 4730: Lecture #27 2 2.5G CDMA Standard  Only one upgrade path for IS-95 CDMA (CDMAOne)  2.5G interim CMDA standard is IS-95B  High-speed packet and circuit switched data access  Original IS-95 data rate was 9.6 kbps »Data rate actually deployed by Sprint PCS and Verizon was 14.4 kbps (IS-95A)  Multiple orthogonal PN spreading codes per user »Each user to take up to 8 different PN spreading codes in parallel »Maximum instantaneous data rate = 8 x 14.4 = 115.2 kbps »Practical data rate was only about 40-64 kbps  Sprint PCS “Wireless Web” »Began use in 2000 using IS-95B

3. ECE 4730: Lecture #27 3 2.5G CDMA Standard  IS-95/IS-95A Soft Handoff  Mobile unit reports RSS back to MSC through current serving BS several hundred times per second  MSC decides when to initiate soft handoff (multiple serving BSs on same radio channel)  IS-95B Hard Handoff  Mobile unit searches for different 1.25 MHz radio channels without approval from MSC  Rapidly tune to new channel if better than serving channel  Hard handoff available in addition to soft handoff  Improves link quality in congested cells where multiple radio channels are being used

4. ECE 4730: Lecture #27 4 2.5G CDMA Standard  IS-95B Upgrade  No new hardware required (baseband or RF)  Only software upgrade at BS  New mobile unit handsets »Backwards compatible with IS-95A

5. ECE 4730: Lecture #27 5 2.5G Standards  2.5G Summary  All designed to overlay on existing 2G networks  No new frequency spectrum required  Practical data rates: »IS-95B  40-64 kbps (packet or circuit switched) »HSCD  57.6 kbps (circuit switched single user) »GPRS  50 kbps (packet switched multi-user) »EDGE  100-120 kbps (packet switched multi-user)  EDGE requires significant new RF hardware and software upgrades »Modulation technique upgraded to 8-PSK

6. ECE 4730: Lecture #27 6 2.5G Standards

7. ECE 4730: Lecture #27 7 3G Wireless  3G Vision  Fully data-centric communication networks  Multi-megabit per second data rates  Voice over Internet Protocol (VoIP)  packet-based voice  Always on access  Applications  Live video and music  Interactive multi-person web sessions  Multi-party conferencing with simultaneous voice and data access

8. ECE 4730: Lecture #27 8 3G Wireless

9. ECE 4730: Lecture #27 9 3G Wireless

10. ECE 4730: Lecture #27 10 3G Wireless  3G History  International Telecommunication Union (ITU) »Formulate truly global 3G standard for 2 GHz band  International Mobile Telephone 2000 (IMT-2000) Plan »Active forum for proposal, development, and debate of global 3G communication standard (started in 1996)  Worldwide user community split into two camps based on 2G outcome: CDMA (IS-95) and GSM (GPRS/EDGE) »Many standards initially proposed and debated but this was narrowed to two leading candidates (most manufacturing support) »3G GSM  Wideband CDMA (W-CDMA)  3G Partnership Project (3GPP) »3G CDMA  CDMA2000  3G Partnership Project 2 (3GPP2)

11. ECE 4730: Lecture #27 11 3G Evolution

12. ECE 4730: Lecture #27 12 3G Wireless  3G Deployment  Countries everywhere allocated new/more spectrum specifically for 3G  Some early 3G spectrum auctions »$35B (USD) in England in 2000  5 nationwide licenses »$46B (USD) in Germany in 2000  4 nationwide licenses  Commercial grade 3G equipment was first deployed in U.S. in 2005  First 3G deployment was 2002 in Japan  Sprint PCS rolled out first US 3G network »CDMA 2000 1xRTT

13. ECE 4730: Lecture #27 13 W-CDMA  3G W-CDMA (UMTS)  Also know as Universal Mobile Telecommunication System (UMTS)  UMTS first started development in 1996 by consortium of European service providers, manufacturers, and governments (ETSI)  Other competing wideband CDMA standards merged with UMTS in 2000  Ensures backwards compatibility with GSM, GPRS, EDGE network structure and bit-level packaging »Completely new CDMA air interface »NOT backwards compatible with baseband and RF hardware in BS »Completely new base stations required

14. ECE 4730: Lecture #27 14 W-CDMA  3G W-CDMA  Minimum of 5 MHz BW required for one RF channel »4 times larger than 1.25 MHz RF BW for IS-95  Multiple RF channels would be required to support large number of high speed users »Requires significant new spectrum  Complete change out of base station RF & baseband hardware  Supports data rates from 8 kbps to 2 Mbps (stationary users only) »Determined by available network capacity and user requirements  100-350 simultaneous voice calls »Depends on channel conditions, user velocity, etc  Future W-CDMA versions (4G) support up to 8 Mbps

15. ECE 4730: Lecture #27 15 W-CDMA  3G W-CDMA  6 times increase in capacity relative to GSM on a system wide basis Example: 200 simultaneous voice calls in 5 MHz  25 kHz/user, GSM 8 users per 200 kHz channel  25 kHz/user, but 100% frequency reuse in W-CDMA vs. N = 4 for GSM  Always on packet based wireless »Computers, PDAs, phones, etc. share network and continuously connected to internet  FDD and TDD modes »Mobile cellular  FDD (separate F/R channels) »Indoor portable/cordless  TDD (1 channel shared in time for F/R)

16. ECE 4730: Lecture #27 16 W-CDMA  3G W-CDMA  Support advanced high data rate services »Streaming audio/video »Videoconferencing »Video games »Broadcast TV!  Public and private network features  Slow and gradual deployment due to new BS hardware and new spectrum »Dual mode or tri-mode phones to support GSM, EDGE, and W- CDMA  W-CDMA was fully installed by 2010

17. ECE 4730: Lecture #27 17 CDMA2000  3G CDMA 2000  Seamless evolutionary path for 2G IS-95 and 2.5G IS-95B »Must retain original 1.25 MHz IS-95 RF BW structure!!  Left over from AMPS carriers not willing to risk more than 10% of their allocated 12.5 MHz spectrum!!  Gradual deployment with existing IS-95 2G and 2.5G systems »Deploy on cell by cell basis »No wholesale hardware changeout »No new spectrum required »Significant advantages/distinctions relative to W-CDMA

18. ECE 4730: Lecture #27 18 CDMA2000  3G CDMA2000  US Telecommunication Industry Association (TIA) oversaw the standard development »Compared to ETSI (European Telecommunication Standards Institute) for W-CDMA »Qualcomm is major developer of CDMA2000  International collaborators as well  First version of CDMA2000 was 1xRTT (1X) »Multi-carrier (multiple RF channels) but first deployment allowed only 1 channel!! »307 kbps maximum data rate and 144 kbps typical throughput  IS-95B has only 40-50 kbps typical throughput

19. ECE 4730: Lecture #27 19 CDMA2000  3G CDMA2000  1xRTT (1X) »Multi-level keying (PSK) and multiple PN spreading sequences  Both are rapidly adaptable based on network capacity, user need, and channel conditions  Incremental redundancy like EDGE! »All changes are baseband signaling changes »No new RF hardware required »All changes done in baseband hardware/software  Cell by cell basis if desired!! »Packet network hardware must also be installed @ MSC »Supports 2 x voice users as IS-95 and double the battery life

20. ECE 4730: Lecture #27 20 CDMA2000  3G CDMA2000  3xRTT (3X) »Multi-carrier CDMA »3 RF carriers  3 x 1.25 MHz = 3.75 MHz cumulative BW »3 adjacent RF carriers (option 1)  Creates single 3.75 MHz channel & requires new RF hardware »3 non-adjacent RF carriers (option 2)  No new RF hardware »Packet data throughput up to 2 Mbps (just like W-CDMA)  Actual rate depends on network capacity, mobile velocity, channel conditions, etc.

21. ECE 4730: Lecture #27 21 3G Wireless  CDMA2000 vs. W-CDMA  US vs. Europe  CDMA2000 had advantages of more seamless, gradual, and economically viable deployment »More rapid rollout of 3G than W-CDMA »Sprint PCS had nationwide 3xRTT in US  W-CDMA had advantage of 4 to 1 GSM-based installed user population »Greater manufacturing support »Less rapid rollout due to RF hardware upgrades

22. ECE 4730: Lecture #27 22 WLAN and WiFi  FCC first allocated unlicensed ISM “garbage” bands in mid 1980’s (also called UNII bands)  Part 15 FCC rules call for low-power (< 1 W) spread spectrum (minimize inter-system interference) devices  902-928 MHz »Digital cordless phones, medical monitors, remote meter reading, baby monitors, bluetooth devices, etc.  2400-2483.5 MHz »Wireless Local Area Networks (WLAN)  No wires required to network computers together in office building  significant time/labor/cost savings  IEEE 802.11 WLAN working group founded in 1987

23. ECE 4730: Lecture #27 23 WLAN and WiFi  Unlicensed ISM/UNII bands  5.725-5.825 MHz »Not used for much  Too high frequency, poorer propagation than 2.4 MHz with  same RF BW (100 MHz vs. 84 MHz)  WLAN interest/use in 2.4 GHz band did not develop until mid-1990s »Widespread use of internet and portable laptop computers »802.11 finally approved in 1997 using DS-SSM  2 Mbps data rate (1 Mbps fallback in “noisy” conditions)  Comparable data rate to 3G wireless!!  International standard ensures interoperability / compatibility between various equipment manufactures  WLAN market expands dramatically

24. ECE 4730: Lecture #27 24 802.11 WiFi  FCC allocates 200 MHz of additional spectrum in 1997 in 5-6 GHz range  5.15-5.35 GHz (along with original 100 MHz from 5.725- 5.825 MHz)  300 MHz total spectrum in 5-6 GHz range  High Data Rate 802.11b approved in 1999  Still for 2.4 GHz band  11 Mbps, 5.5 Mbps in addition to 2 and 1 Mbps from earlier version  Commercial name of 802.11b is “Wi-Fi” for “Wireless Fidelity”

25. ECE 4730: Lecture #27 25 802.11 WiFi  ABC’s of 802.11  Popularity of 802.11 has led to development of more versions for increased functionality  802.11a »Data rates from 6 to 54 Mbps throughput for 5 GHz band »Fastest data rates in 802.11 »OFDM modulation  802.11e  QoS issues for real-time (video) applications  802.11f  roaming between multiple WLAN access points  802.11i  increased security and advanced encryption »802.11a and b were initially easily hacked into

26. ECE 4730: Lecture #27 26 802.11 Future  802.11 Future  Significant competition with 3G wireless »Higher data rates than 3G »Hardware much cheaper to purchase and install  Wireless Internet Service Provider (WISP) »Nationwide infrastructure of WLAN access points  Airports, coffee shops (e.g. Starbucks), hotels, etc. »Charge monthly subscription fee  Provide wireless internet for last 100 meters into homes, businesses, etc.  Convergence between 3G and WiFi »Dual mode 3G and WiFi enabled phones »Roaming agreements between 3G and WiFi providers