Communication Networks Chapter 9: UMTS

Transcription

1 Communication Networks Chapter 9: UMTS o IMT-2000 o UMTS Architecture o UTRAN Architecture o UMTS Mobility Support o UMTS Development UMTS and IMT-2000 Proposals for IMT-2000 (International Mobile Telecommunications) UWC-136, cdma2000, WP-CDMA UMTS (Universal Mobile Telecommunications System) from ETSI UMTS UTRA (was: UMTS, now: Universal Terrestrial Radio Access) enhancements of GSM EDGE (Enhanced Data rates for GSM Evolution): GSM up to 384 kbit/s CAMEL (Customized Application for Mobile Enhanced Logic) VHE (virtual Home Environment) fits into GMM (Global Multimedia Mobility) initiative from ETSI requirements min. 144 kbit/s rural (goal: 384 kbit/s) min. 384 kbit/s suburban (goal: 512 kbit/s) up to 2 Mbit/s urban Communication Networks - 9: UMTS 373 Prof. Jochen Seitz 1

2 Frequencies for IMT-2000 ITU allocation (WRC 1992) MHz IMT-2000 IMT-2000 Europe GSM 1800 DE CT T D D UTRA FDD T D D UTRA FDD China GSM 1800 IMT-2000 IMT-2000 Japan cdma2000 PHS W-CDMA cdma2000 W-CDMA North America PCS MHz rsv. Communication Networks - 9: UMTS 374 IMT-2000 Family Interface for Internetworking IMT-2000 Core Network ITU-T GSM (MAP) ANSI-41 (IS-634) IP-Network Initial UMTS (R99 w/ FDD) Flexible assignment of Core Network and Radio Access IMT-2000 Radio Access ITU-R IMT-DS (Direct Spread) UTRA FDD (W-CDMA) 3GPP IMT-TC (Time Code) UTRA TDD (TD-CDMA); TD-SCDMA 3GPP IMT-MC (Multi Carrier) cdma2000 3GPP2 IMT-SC (Single Carrier) UWC-136 (EDGE) UWCC/3GPP IMT-FT (Freq. Time) DECT ETSI Communication Networks - 9: UMTS 375 Prof. Jochen Seitz 2

3 GSM and UMTS Releases Stages (0: feasibility study) 1: service description from a serviceuser s point of view 2: logical analysis, breaking the problem down into functional elements and the information flows amongst them 3: concrete implementation of the protocols between physical elements onto which the functional elements have been mapped (4: test specifications) Note "Release 2000" was used only temporarily and was eventually replaced by "Release 4" and "Release 5" Additional information: SpecReleaseMatrix.htm Rel Spec version number Functional freeze date, indicative only Rel x.y Stage 1 freeze March 2013 Stage 2 freezedecember 2013 Stage 3 freeze June 2014 Rel x.y Stage 1 freeze September 2011 Stage 2 freeze March 2012 Stage 3 freeze September 2012 (protocols stable December 2012 / March 2013) Rel x.y Stage 1 freeze March 2010 Stage 2 freeze September 2010 Stage 3 freeze March 2011 (protocols stable three months later) Rel-9 9.x.y Stage 1 freeze December 2008 Stage 2 freeze June 2009 Stage 3 freeze December 2009 Rel-8 8.x.y Stage 1 freeze March 2008 Stage 2 freeze June 2008 Stage 3 freeze December 2008 Rel-7 7.x.y Stage 1 freeze September 2005 Stage 2 freeze September 2006 Stage 3 freeze December 2007 Rel-6 6.x.y December March 2005 Rel-5 5.x.y March - June 2002 Rel-4 4.x.y March 2001 R00 4.x.y see note 1 below 9.x.y R99 3.x.y March 2000 (closed June 2011) Communication Networks - 9: UMTS 376 Licensing Example: UMTS in Germany, August 18, 2000 UTRA-FDD: Uplink MHz Downlink MHz duplex spacing 190 MHz 12 channels, each 5 MHz UTRA-TDD: MHz, MHz; 5 MHz channels Coverage of the population 25% until 12/ % until 12/2005 Sum: billion Communication Networks - 9: UMTS 377 Prof. Jochen Seitz 3

4 UMTS Architecture (Release 99 used here!) UTRAN (UTRA Network) Cell level mobility Radio Network Subsystem (RNS) Encapsulation of all radio specific tasks UE (User Equipment) CN (Core Network) Inter system handover Location management if there is no dedicated connection between UE and UTRAN U u I u UE UTRAN CN Communication Networks - 9: UMTS 378 UMTS Domains and Interfaces I Home Network Domain Z u USIM Domain C u Mobile U u Access I u Equipment Network Domain Domain Serving Network Domain Y u Transit Network Domain Core Network Domain User Equipment Domain Infrastructure Domain User Equipment Domain Assigned to a single user in order to access UMTS services Infrastructure Domain Shared among all users Offers UMTS services to all accepted users Communication Networks - 9: UMTS 379 Prof. Jochen Seitz 4

5 UMTS Domains and Interfaces II Universal Subscriber Identity Module (USIM) Functions for encryption and authentication of users Located on a SIM inserted into a mobile device Mobile Equipment Domain Functions for radio transmission User interface for establishing/maintaining end-to-end connections Access Network Domain Access network dependent functions Core Network Domain Access network independent functions Serving Network Domain Network currently responsible for communication Home Network Domain Location and access network independent functions Communication Networks - 9: UMTS 380 Spreading and Scrambling of User Data Constant chipping rate of 3.84 Mchip/s Different user data rates supported via different spreading factors higher data rate: less chips per bit and vice versa User separation via unique, quasi orthogonal scrambling codes users are not separated via orthogonal spreading codes much simpler management of codes: each station can use the same orthogonal spreading codes precise synchronization not necessary as the scrambling codes stay quasiorthogonal data 1 data 2 data 3 data 4 data 5 spr. code 1 spr. code 2 spr. code 3 spr. code 1 spr. code 4 scrambling code 1 scrambling code 2 sender 1 sender 2 Communication Networks - 9: UMTS 381 Prof. Jochen Seitz 5

6 OVSF Coding X 1,1,1,1 1,1 1,1,-1,-1 X,X 1 X,-X 1,-1,1,-1 1,1,1,1,1,1,1,1 1,1,1,1,-1,-1,-1,-1 1,1,-1,-1,1,1,-1,-1 1,1,-1,-1,-1,-1,1,1 1,-1,1,-1,1,-1,1, SF=n SF=2n 1,-1 1,-1,-1,1 1,-1,1,-1,-1,1,-1,1 1,-1,-1,1,1,-1,-1,1 1,-1,-1,1,-1,1,1,-1... SF=1 SF=2 SF=4 SF=8 Orthogonal Variable Spreading Factor Communication Networks - 9: UMTS ms µs µs µs UMTS FDD Frame Structure Radio frame Time slot Pilot TFCI FBI TPC Data chips, 10 bits Data 2560 chips, 10*2 k bits (k = 0...6) TPC TFCI Data 2 Pilot DPDCH DPCCH DPDCH DPCCH 2560 chips, 10*2 k bits (k = 0...7) Slot structure NOT for user separation but synchronization for periodic functions! uplink DPCCH uplink DPDCH downlink DPCH W-CDMA MHz uplink MHz downlink chipping rate: Mchip/s soft handover QPSK complex power control (1500 power control cycles/s) spreading: UL: 4-256; DL:4-512 FBI: Feedback Information TPC: Transmit Power Control TFCI: Transport Format Combination Indicator DPCCH: Dedicated Physical Control Channel DPDCH: Dedicated Physical Data Channel DPCH: Dedicated Physical Channel Communication Networks - 9: UMTS 383 Prof. Jochen Seitz 6

7 Typical UTRA-FDD Uplink Data Rates User data rate [kbit/s] 12.2 (voice) DPDCH [kbit/s] DPCCH [kbit/s] Spreading Communication Networks - 9: UMTS 384 UMTS TDD Frame Structure (Burst Type 2) Radio frame 10 ms Time slot µs Data 1104 chips Midample 256 chips 2560 chips Data 1104 chips GP Traffic burst GP: guard period 96 chips TD-CDMA 2560 chips per slot spreading: 1-16 symmetric or asymmetric slot assignment to UL/DL (min. 1 per direction) tight synchronization needed simpler power control ( power control cycles/s) Communication Networks - 9: UMTS 385 Prof. Jochen Seitz 7

8 UTRAN Architecture UE 1 I ub RNS RNC: Radio Network Controller RNS: Radio Network Subsystem I u RNC CN UE 3 UE 2 I ub I ur RNC RNS UTRAN comprises several RNSs can support FDD or TDD or both RNC is responsible for handover decisions requiring signaling to the UE Cell offers FDD or TDD Communication Networks - 9: UMTS 386 UTRAN Functions Admission control Congestion control System information broadcasting Radio channel encryption Handover SRNS moving Radio network configuration Channel quality measurements Macro diversity Radio carrier control Radio resource control Data transmission over the radio interface Outer loop power control (FDD and TDD) Channel coding Access control Communication Networks - 9: UMTS 387 Prof. Jochen Seitz 8

9 Core Network: Protocols VLR RNS MSC GSM-CS backbone GMSC PSTN/ ISDN HLR RNS Layer 3: IP Layer 2: ATM Layer 1: PDH, SDH, SONET SGSN GPRS backbone (IP) SS 7 GGSN PDN (X.25), Internet (IP) UTRAN CN Communication Networks - 9: UMTS 388 Core Network: Architecture BTS A bis BSS I u VLR BSC MSC GMSC PSTN TS B I u CS AuC EIR HLR I ub GR RNC SGSN G n GGSN G i RNS I u PS CN Communication Networks - 9: UMTS 389 Prof. Jochen Seitz 9

10 Core Network The Core Network (CN) and thus the Interface I u, too, are separated into two logical domains: Circuit Switched Domain (CSD) Circuit switched service incl. signaling Resource reservation at connection setup GSM components (MSC, GMSC, VLR) I u CS Packet Switched Domain (PSD) GPRS components (SGSN, GGSN) I u PS Release 99 uses the GSM/GPRS network and adds a new radio access! Helps to save a lot of money Much faster deployment Not as flexible as newer releases (5, 6) Communication Networks - 9: UMTS 390 UMTS Protocol Stacks (User Plane) Circuit switched UE U u UTRAN I u CS 3G MSC apps. & protocols RLC MAC RLC MAC SAR AAL2 SAR AAL2 radio radio ATM ATM Packet switched UE U u UTRAN I u PS 3G apps. & protocols SGSN IP, PPP, IP tunnel PDCP PDCP GTP GTP GTP RLC RLC UDP/IP UDP/IP UDP/IP MAC radio MAC radio AAL5 ATM AAL5 ATM L2 L1 G n 3G GGSN IP, PPP, GTP UDP/IP L2 L1 Communication Networks - 9: UMTS 391 Prof. Jochen Seitz 10

11 Support of Mobility: Macro Diversity UE RNC CN Multicasting of data via several physical channels Enables soft handover FDD mode only Uplink simultaneous reception of UE data at several s Reconstruction of data at, SRNC or DRNC Downlink Simultaneous transmission of data via different cells Different spreading codes in different cells Communication Networks - 9: UMTS 392 Support of Mobility: Handover From and to other systems (e.g., UMTS to GSM) This is a must as UMTS coverage will be poor in the beginning RNS controlling the connection is called SRNS (Serving RNS) RNS offering additional resources (e.g., for soft handover) is called Drift RNS (DRNS) End-to-end connections between UE and CN only via I u at the SRNS Change of SRNS requires change of I u Initiated by the SRNS Controlled by the RNC and CN SRNC CN UE I ub I ur I u DRNC I ub Communication Networks - 9: UMTS 393 Prof. Jochen Seitz 11

12 Example Handover Types in UMTS/GSM UE 1 1 RNC 1 3G MSC 1 UE 2 2 I ub I ur I u UE 3 3 RNC 2 3G MSC 2 UE 4 BTS BSC 2G MSC 3 A bis A Communication Networks - 9: UMTS 394 Breathing Cells GSM Mobile device gets exclusive signal from the base station Number of devices in a cell does not influence cell size UMTS Cell size is closely correlated to the cell capacity Signal-to-nose ratio determines cell capacity Noise is generated by interference from other cells other users of the same cell Interference increases noise level Devices at the edge of a cell cannot further increase their output power (max. power limit) and thus drop out of the cell no more communication possible Limitation of the max. number of users within a cell required Cell breathing complicates network planning Communication Networks - 9: UMTS 395 Prof. Jochen Seitz 12

13 Breathing Cells: Example Communication Networks - 9: UMTS 396 UMTS Services (Originally) Data transmission service profiles Service Profile High Interactive MM High MM Medium MM Switched Data Simple Messaging Voice Bandwidth 128 kbit/s 2 Mbit/s 384 kbit/s 14.4 kbit/s 14.4 kbit/s 16 kbit/s Transport mode Circuit switched Packet switched Circuit switched Circuit switched Packet switched Circuit switched Bidirectional, video telephone Low coverage, max. 6 km/h asymmetrical, MM, downloads SMS successor, Virtual Home Environment (VHE) Enables access to personalized data independent of location, access network, and device Network operators may offer new services without changing the network Service providers may offer services based on components which allow the automatic adaptation to new networks and devices Integration of existing IN services Communication Networks - 9: UMTS 397 Prof. Jochen Seitz 13

14 Example 3G Networks: Japan FOMA (Freedom Of Mobile multimedia Access) in Japan Examples for FOMA phones Communication Networks - 9: UMTS 398 Isle of Man Start of UMTS in Europe as Test Communication Networks - 9: UMTS 399 Prof. Jochen Seitz 14

15 UMTS in Monaco Communication Networks - 9: UMTS 400 UMTS in Europe Orange/UK Vodafone/Germany Communication Networks - 9: UMTS 401 Prof. Jochen Seitz 15

16 Some current enhancements I GSM Enhanced Message Service EMS / Multimedia Messaging Service MMS EMS: 760 characters possible by chaining SMS, animated icons, ring tones, was soon replaced by MMS (or simply skipped) MMS: transmission of images, video clips, audio see WAP 2.0 EDGE (Enhanced Data Rates for Global [was: GSM] Evolution) 8-PSK instead of GMSK, up to 384 kbit/s new modulation and coding schemes for GPRS EGPRS MCS-1 to MCS-4 uses GMSK at rates 8.8/11.2/14.8/17.6 kbit/s MCS-5 to MCS-9 uses 8-PSK at rates 22.4/29.6/44.8/54.4/59.2 kbit/s Communication Networks - 9: UMTS 402 Some current enhancements II UMTS HSDPA (High-Speed Downlink Packet Access) initially up to 10 Mbit/s for the downlink, later > 20 Mbit/s using MIMO- (Multiple Input Multiple Output-) antennas can use 16-QAM instead of QPSK (ideally > 13 Mbit/s) user rates e.g. 3.6 or 7.2 Mbit/s HSUPA (High-Speed Uplink Packet Access) initially up to 5 Mbit/s for the uplink user rates e.g Mbit/s Communication Networks - 9: UMTS 403 Prof. Jochen Seitz 16

17 Some current enhancements III LTE (Long Term Evolution) Generation 3.9 Peak data rates of 300 Mb/s (downlink) and 75 Mb/s (uplink) LTE Advanced / LTE + increased peak data rate, downlink 3 Gbit/s, uplink 1.5 Gbit/s higher spectral efficiency, from a maximum of 16bps/Hz in R8 to 30 bps/hz in R10 increased number of simultaneously active subscribers improved performance at cell edges, e.g. for DL 2x2 MIMO at least 2.40 bps/hz/cell. Communication Networks - 9: UMTS th Generation Tactile Internet Said to be introduced in the early 2020s IMT 2020 Main goals: Efficiency with low cost High bit rate using dynamic spectrum access Convergence of fiber and wireless network Application scenarios Internet of Things (IoT) Integration of MANETs Communication Networks - 9: UMTS 405 Prof. Jochen Seitz 17

18 References SCHILLER, J.: Mobile Communications, 2nd edition, Addison-Wesley, 2003, ISBN (Thanks for the Powerpoint Slides) Communication Networks - 9: UMTS 406 Prof. Jochen Seitz 18