Wireless Communications Lecture-4: Evolution of Cellular Communication Systems

1. University of Palestine International Faculty of Information Technology Wireless Communications Lecture-4: Evolution of CellularCommunication Systems week 4- Semester-2/ 2008 Dr. Anwar Mousa

2. MOBILE SYSTEMS EVOLUTIONTHIRD GENERATION • Basically a linear enhancement of 2G systems. • Based on twoparallel backbone infrastructures: • Circuit switched nodes, • Packet oriented nodes.

3. MOBILE SYSTEMS EVOLUTIONTHIRD GENERATION • This process of standard harmonization produced three modes of operation: • CDMA-DS (CDMA - Direct Sequence) based on UMTS Frequency Division Duplex (FDD) • CDMA-MC (CDMA - Multi Carrier) based on CDMA2000 • CDMA-TDD(CDMA - Time Division Duplex) based on UMTS TDD

4. MOBILE SYSTEMS EVOLUTIONFOURTH GENERATION • In general, A NEW GENERATION is defined by the result of technology changes over a 10–15 year time frame. • Thus, 4G refers to whatever is deployed in the 2010–2015 period, • assuming 3G deployment spans the 2000–2009 period. • However, 3G is regarded by many as being "a bit of a flop“ • so telecommunications companies are planning to roll out 4G earlier (possibly as early as 2008).

5. MOBILE SYSTEMS EVOLUTIONFOURTH GENERATION • Typically, a new standard means a new air-interface with • higher data rates in the least, • change in the way data transport is handled end-to-end. • The infrastructure and the terminals will have almost all the standards from 2G to 3G implemented. • The infrastructure will however only be packet based, all-IP.

6. MOBILE SYSTEMS EVOLUTIONFOURTH GENERATION • The system will also serve as an Open Platform where • New innovations can go with it • Some of the standards which pave the way for 4G systems are • WiMax, Worldwide Interoperability for Microwave Access • WiBro, The Koreans alternative to 3.5G or 4G cellular systems • 3GPPLTE 3G Partnership Project Long Term Evolution • release 8 of the UMTS work-in-progress technologies such as HSOPA.(HSDPA, HSUPA)

7. Contents: • THIRD GENERATION SYSTEMS • UMTS Main characteristics • UMTS architecture • UMTS Frequencies • UMTS Location Based Services • UMTS Security • CDMA Overview • CDMA Coding • The spreading process • WCDMA

8. 3 Third-Generation Mobile SystemsMain Features The main Features of 3G systems, known collectively as IMT–2000, are single family of compatible standards Characteristics: • Used worldwide • Used for all mobile applications • Support both packet switched (PS) and circuit switched (CS) data • Offer high data rates up to 2 Mbps (depending on mobility/velocity) • Offer high spectrum efficiency

9. StandardHarmonization • Standard harmonization produced three modes of operation: • CDMA-DS (CDMA - Direct Sequence) based on UMTS Frequency Division Duplex (FDD) • CDMA-MC (CDMA - Multi Carrier) based on CDMA2000 • CDMA-TDD (CDMA - Time Division Duplex) based on UMTS TDD

10. UMTS -Main characteristics • The most important IMT–2000 proposals are the UMTS (W-CDMA) as the successor to GSM. • To reach global acceptance, 3GPP is introducing UMTS in annual releases. • The first release (UMTS Rel. ’99), introduced in 1999, • enhancements and transitions for existing GSM networks. • The second release(UMTS Rel. ’00), • enhancements for IS–95 (with CDMA2000) and TDMA (with EDGE). • UMTS includes both terrestrial and satellite systems to support universal roaming and global coverage.

11. UMTS -Main characteristics cont… • The most significant change in Rel. ’99 is • the new UMTS terrestrial radio access (UTRA),a W–CDMA radio interface for land-based communications. • UTRA supports (TDD) and (FDD). • The TDD mode is optimized for public micro and pico cells • The FDD mode is optimized for wide-area coverage • Another newly defined UTRA mode, multicarrier (MC), established compatibility between UMTS and CDMA2000.

12. Evolutionary Concept

13. UMTS -Main characteristics cont… • More than 60 3G/UMTS networks using WCDMA technology are operating commercially in 25 countries. • Japanese operator NTT DoCoMo launched the world's first commercial WCDMA network in 2001. • 3G/UMTS employs a 5 MHz channel carrier width • Operators are usually granted blocks of spectrum - typically ranging from 2x10 MHz up to 2x20 MHz.

14. UMTS -Main characteristics cont… • UMTS supports the virtual home environment(VHE) concept. • UMTS supports four types of traffic: • Conversational class (voice, video telephony, video gaming) • Streaming class (multimedia, video on demand, webcast) • Interactive class (web browsing, network gaming, database access) • Background class (email, SMS, downloading)

15. UMTS –Data rates • UMTS employs a Hierarchical Cell Structure • Macrocells overlaying microcells and picocells. • Highly mobile traffic is operated on the macrocells to reduce the number of handoffs.

16. Hierarchical Cell Structure

17. UMTS –Data rates • Offered data rate targets are: • 144 kbits/ssatellite and rural outdoor • 384 kbits/surban outdoor • 2048 kbits/s indoor and low range outdoor

18. UMTS –Data rates • The data rate supported by 3G networks depends on the environment the call is being made in

19. UMTS architecture • The UMTS architecture is split into: • Core (switching) network: • performing switching and transmission functions. • contains the databases and network management functions. • UMTS Terrestrial Radio Access Network (UTRAN): • provides channel access to mobile users • performs radio resource management and signalling • User Equipment: • based on the same principles as the GSM MS • Contains UMTS subscriber identity module card (USIM).

20. GSM network architecture

21. GPRS Architecture • .

22. UMTS architecture

23. UMTS-Core Network • The basic Core Network architecture for UMTS is based on GSM network with GPRS. • However, all equipment has to be modified for UMTS operation and services. • The Core Network is divided in circuit switched and packet switched domains. • Some of the circuit switched elements are (MSC), (VLR) and Gateway MSC. • Packet switched elements are (SGSN) and (GGSN). • Some network elements, like EIR, HLR, and AUC are shared by both domains.

24. UMTS- UTRAN • UMTS differs from GSM Phase 2+ mostly in the new principles for air interface transmission • (W–CDMA instead of TDMA/ FDMA). • The UTRAN (UMTS Terrestrial Radio Access Network, based on W–CDMA )provides the air interface access method for User Equipment. • Two new network elements are introduced in UTRAN, • RNC (Radio Network Controller) • The RNC is connected to a set of Node B elements, each of which can serve one or several cells. • Node B

25. UMTS- UTRAN • The UMTS Terrestrial Radio Access System (UTRA) provides at least: • 144 kbps for full-mobility applications, • 384 kbps for limited-mobilityapplications, • 2.048 Mbps for low-mobility applications.

26. UMTS- UTRAN

27. UTRAN-Node B • Existing network elements, such as MSC, SGSN, and HLR, can be extended to adopt the UMTS requirements • but RNC, Node B, and thehandsets must have completely new designs. • Node B is the physical unit for radio transmission/reception with cells. • Depending on sectoring (omni/sector cells), one or more cells may be served by a Node B.

28. UTRAN-Node B • A single Node B can support both FDD and TDD modes • It can be co-located with a GSM BTS to reduce implementation costs. • Node B connects with the UE via the W–CDMA Uu radio interface • Node B connects with the RNCvia the Iub asynchronous transfer mode (ATM)–based interface. • Node B is the ATM termination point.

29. UTRAN-Node B .

30. UTRAN-User Equipment • UMTS terminals (User Equipment-UE) are multiband and multimode • so that they can work with different standards. • UE has many different types of identities: • International Mobile Subscriber Identity (IMSI) • Temporary Mobile Subscriber Identity (TMSI) • Packet Temporary Mobile Subscriber Identity (P-TMSI) • Temporary Logical Link Identity (TLLI) • Mobile station ISDN (MSISDN) • International Mobile Station Equipment Identity (IMEI) • International Mobile Station Equipment Identity and Software Number (IMEISV)

31. UMTS-Frequencies • 1920-1980 and 2110-2170MHz (FDD, W-CDMA) Paired uplink and downlink, • Channel spacing is 5 MHz and raster is 200 kHz. • An Operator needs 3 - 4 channels (2x15 MHz or 2x20 MHz) to be able to build a high-speed, high-capacity network. • 1900-1920 and 2010-2025MHz (TDD, TD/CDMA) Unpaired, • channel spacing is 5 MHz and raster is 200 kHz. • Tx and Rx are not separated in frequency. • 1980-2010 and 2170-2200 MHzSatellite uplink and downlink.

32. UMTS-Frequencies UTRA FDD frequency bands TX-RX frequency separation

33. UMTS Location Based Services • UMTS networks supports location service features. • Identify and report in a standard format (geographical co-ordinates) the current location of the user's terminal • Make the information available to the user, network operator, and service provider. • The location is to be used for lawful interception, emergency calls, etc., as well as the positioning services.

34. UMTS Location Based Services, cont… • Location Information consists of: • Geographic Location • Velocity (the combination of speed and heading ) • Quality of Service information (response time) • Specifications specify the following positioning methods: • Cell coverage based positioning method • Observed Time Difference Of Arrival (OTDOA) method • Network assisted GPS methods.

35. OTDOA Location Method