3G/Third Generation Wireless EECS4215 – Mobile Communications York University 1

Outline 3G Systems and IMT-2000 Universal Mobile Telecommunications System (UMTS) Wideband Code Division Multiple Access (W- CDMA) Technology CDMA2000 2

3G Systems and IMT-2000 Global mobility with a wide range of services: – Telephony; Messaging; Internet; Data transport ITU define the standard for 3G systems: – International Mobile Telecommunication 2000 In 1998, the Third Generation Partnership Project (3GPP) to continue the technical specification work for a 3G standard. 3

UMTS Standardization Process In Europe, the European Telecom Standards Institute (ETSI) was responsible for the UMTS standardization process. Centerpiece of the 3G evolution. Using GSM standards for its networks architecture and wideband CDMA (W-CDMA) as its air interface technology. 4

Data Rates Specified for 3G Services Mbps for picocell applications. 384 Kbps for medium-size cells (micro and macro). 144 and 64 Kbps for large cells (large macro) Kbps for continuous low-speed data applications in very large cells Kbps for speech (4.75 – 12.2 Kbps). 9.6 Kbps globally (satellite). New technologies will coexist with previous technology equipment in base station shelters. 5

Universal Mobile Telecommunications System (UMTS) A broadband, packet-based 3G standard. Transmission of text, digitized voice, video and multimedia at data rates of up to 2 Mbps. Based on GSM standard. Use packet-switched connection using Internet Protocol (IP). Developed mainly for countries with operational GSM networks. 6

Development of UMTS Standard The 3GPP wisely kept the core network as close as the GSM core network specifications. Has two types of operations: – FDD: Different frequencies are used for up and down links – TDD: One frequency is used in both up and down links TDD has strong advantage over FDD where there is asymmetry of the up and down links data rates. 7

Characteristics of UMTS UMTS is superior to 2G technologies because of following characteristics: – Higher speech quality – Supports 2 Mbps data rates – Also have Virtual Home Environment (VHE): users are presented with the same personalized features consistently everywhere – Improved network security and location based services. 8

Migration Path to 3G/UMTS from 2G Technologies 9

UMTS Networks Architecture A UMTS network consists of three interacting domains: 1.The core network (CN) – switching, routing – HLR, VLR – element management system (EMS): manages network elements such as BS equipment, network radio controllers (RNCs), the switch, peripherals. 1.The UMTS terrestrial radio access network (UTRAN) – provides access to network via W-CDMA 1.User equipment (UE) (i.e. mobile phone) 10

UMTS Networks Architecture (2) UMTS networks operate as an overlay to GSM/EDGE networks. UMTS radio equipment is installed side-by-side with GSM-based equipment. Core network: based on GSM architecture – uses GPRS/EDGE as the data network foundation The base station in UMTS is called Node-B. Radio network controller (RNC): control equipment for Node-Bs (equivalent to BSC in GSM) 11

UTMS Network Architecture The UTMS Network Architecture. Note the separation of the circuit-switched and packet-switched domains, and how 2G and 3G network elements operate in parallel. Also note how some network elements are shared in both the 2G and 3G domains. 12

Geographic Boundaries in UMTS It is important to know users’ approximate locations Division of geographic boundaries in UMTS into “system areas”, from largest to smallest: – UMTS systems – Public land mobile network (PLMN) – MSC/VLR or serving GPRS support node (SGSN) – Location area – Routing area (packet-switched domain) – UTRAN registration area (packet-switched domain) – Cell – Subcell 13

UMTS QoS Classes UMTS services have different quality of service classes for four types of traffic: – Conversational class (voice, video telephony and gaming) – Streaming class (multimedia, video on demand, webcast) – Interactive class (web browsing, network gaming, database access) – Background class ( , SMS, downloading) 14

The UMTS Core Network Based on GSM network technology, GPRS/EDGE as the data network foundation Provide switching routing for user traffic: – Circuit-switched (CS) domain – Packet-switched (PS) domain Contains the databases and network management functions: HLR, VLR, EMS 15

The UMTS Core Network (2) Voice transmissions are routed to the CS domain. Packet-based transmissions are routed to the PS domain. Some of the circuit-switched elements are the MSC, the VLR and the gateway MSC. Elements supporting GPRS/EDGE technology. A number portability database (NPDB) is used to allow users to change network providers while keeping their phone number. 16

UTMS Network Architecture The UTMS Network Architecture. Note the separation of the circuit-switched and packet-switched domains, and how 2G and 3G network elements operate in parallel. Also note how some network elements are shared in both the 2G and 3G domains. 17

The UMTS Terrestrial Radio Access Network (UTRAN) RNCs connect – voice calls to mobile switching centers (MSCs) – data sessions to packet data service nodes (PDSNs). The UTRAN core network is divided into: – Circuit switched (primary voice) domain – Packed switched (primary data) domain The MTSO connects to the UTRAN system The gateway MSC (GMSC) connects to the PSTN 18

Functions of the UMTS Base Station (Node-B) Air interface transmission and reception. Modulation and demodulation of all transmissions. CDMA physical channel coding. Error management. Power control. 19

Functions of the RNC Radio resource control. Admission control-granting access to the network. Channel allocation. Power control settings (imperative to maintain system capacity). Handover (handoff) control and ciphering (encryption). Segmentation and reassembly of packet-based transmissions. Broadcast signaling. 20

User Equipment (UE) UE: mobile phones, UMTS mobile terminals Mobile phones will automatically seek a UMTS-based frequency/channel first; then “step down” to GSM if UMTS capacity is not available. 21

Functions of UMTS IC Card Same physical characteristics as SIM cards in GSM Support of one user service identity module (USIM) application (optionally more than one). Support of one or more user profiles on the SIM Update USIM specific information over the air. Security functions User authentication Optional inclusion of payment methods and secure downloading of new applications 22

Wideband Code Division Multiple Access (W-CDMA) Technology W-CDMA has two basic modes of operation: – FDD: different frequencies are used for up and down links; used for both voice and data – TDD: one frequency is used in both up and down links; for systems with no dual frequency bands It’s the radio air interface technology of UMTS. First launched in 2001: – “Narrowband” CDMA uses a 1.25-MHz carrier – “Wideband” CDMA uses a 5-MHz-wide carrier Like CDMA, W-CDMA is a spread-spectrum modulation technique. 23

CDMA2000 Falls under specification known as IS North American version of W-CDMA. 3G CDMA2000 systems deploy more CDMA carriers per base station: – Possibly 6 – 8 carriers to accommodate the additional bandwidth requirements of 3G systems. cdmaOne, the CDMA2000 2G predecessor technology, is still active in today’s network but likely be sunset by carriers by around

CDMA2000 (2) Most all CDMA2000 networks were 3G upgrades from existing cdmaOne networks (IS-95A/B). The radio channel bandwidth is the same for CDMA2000-1x as for existing cdmaOne channels (a 1.25-MHz carrier), leading to graceful upgrade. – “1x” means the same bandwidth as cdmaOne CDMA2000 1xEV-DO was developed to be backward compatible with cdmaOne (IS-95A/B). 25

CDMA2000-1x (1xRTT) Categories 1.1xEV (enhanced voice only; first version of 1x). 2.1xDO (one carrier supporting data services only). 3.1xDV (one carrier supporting both data and voice services). The 1xRTT platform still uses a 1.25-MHz carrier, but it uses a different vocoder than legacy cdmaOne platforms and introduces more Walsh codes (128 instead of 64): – The additional Walsh codes support higher data rates and more voice conversations than was with cdmaOne platform 26

CDMA2000 Network Architecture 27