Introduction CS 515 Mobile and Wireless Networking Ibrahim Korpeoglu Computer Engineering Department Bilkent University, Ankara CS 515 Ibrahim Korpeoglu 1
Outline n n Course Info Introduction q q n n What is Wireless What is PCS History of Wireless Some Mobile Statistics CS 515 Ibrahim Korpeoglu 2
Course Information CS 515 Ibrahim Korpeoglu 3
Course Details Instructor: Ibrahim Korpeoglu Email: korpe@cs. bilkent. edu. tr Class Hours: Wed 15: 40 -16: 30 Fri: 13: 40 -15: 30 Office Hours Thu 10: 40 -12: 00 Classroom: EA 502 (You can also come to my office at any time if you need to see me) CS 515 Ibrahim Korpeoglu 4
Recommended Textbooks n n Theodore Rappaport, Wireless Communications: Principles and Practice, Second Edition, Prentice Hall, December 2001. Yi-Bing Lin, Imrich Chlamtac, Wireless and Mobile Network Architectures, John Wiles & Sohns, 1 st edition, 2000. n CS 515 You don’t have to buy these books. But I recommend buying them if you have the opportunity! Ibrahim Korpeoglu 5
Reading List n n You will read a lot of papers in this course The papers are on the course web page q q q n You can download them from there. If a paper is not there, let me know. I will put the paper on my door if there is no online copy of the paper The paper-list size on the webpage will be reduced, so that you don’t spend all of your time only on this course. CS 515 Ibrahim Korpeoglu 6
Grading n n There will be one midterm and one final exam There may be projects. I did not determine them yet. q q q n Simulation or implementation projects No idea how hard they will be! No idea which language(s) they will be implemented on! Attendance is important! CS 515 Ibrahim Korpeoglu 7
Why projects are important? n I hear and I forget, I see and I remember, I do and I understand Confucius CS 515 Ibrahim Korpeoglu 8
Outline n Introduction q q What is wireless and mobile networking History of Wireless Challenges of Mobile and Wireless Communication and Networking What is Personal Communications Systems n n q CS 515 Why there is demand on that What is ubiquitous computing. Overview of Wireless Technologies and Systems Ibrahim Korpeoglu 9
Outline n Wireless Link Characteristics q q q q CS 515 Radio Propagation Short and Long wave properties Attenuation Interfence Fading and Multi-path Fading Transmit power and range Bit Error Rate and Models Ibrahim Korpeoglu 10
Outline n Wireless Media Access q What is different in Wireless Media than Wireline Media n n q q CS 515 Why CSMA/CD does not work MACA and MACAW protocols TDMA and FDMA CDMA Ibrahim Korpeoglu 11
Outline n Handoff n n More from telecom point view How handoffs are triggered How handoffs are managed Routing n n n CS 515 more from data networking point of view How mobility affect routing for mobile hosts Mobile IP Ibrahim Korpeoglu 12
Outline n Transport Protocols over Wireless and Mobile Networks n n n CS 515 How does wireless links and mobile hosts affect the performance and operation of transport protocols Look specifically to TCP There are many proposals to improve the performance of TCP over wireless links and for mobile hosts Ibrahim Korpeoglu 13
Outline n Ad-Hoc Mobile Networks n n What if the mobile hosts are not roaming around an infrastructure-based network Ad-hoc networks are established spontaneounly q q n Routing protocols for ad-hoc networks q q CS 515 There is no infrastructure that you can rely on A mobile terminal may also act as an network router Network connectivity graph is not fixed; dynamically changes over time The network elements are small-capacity, battery-powered devices Ibrahim Korpeoglu 14
Outline n Looking closely to the wireless systems q Wireless Local Area Networks n q Wireless Personal Area Networks and Home Networking n q Bluetooth and Home. RF Wide-Area Wireless Cellular Networks n n CS 515 802. 11 and Hiper. LAN Standards GSM CDMA GPRS 3 G Networks Ibrahim Korpeoglu 15
Outline n Wireless and Mobile Applications q q Wireless Application Protocol Mobile Applications n n Mobile Databases Quality of Service in Mobile/Wireless Networks n CS 515 What are the challenges for providing Qo. S in mobile and wireless environments Ibrahim Korpeoglu 16
Outline n Service and Device Discover in Mobile Networks n n How can you discover the resources around you Service Location Protocol Jini Power Management n n CS 515 How low-power objective affect the design of wireless systems and network protocols Issues and solutions Ibrahim Korpeoglu 17
Outline n Introduction to Peer 2 peer networking q q q n What is peer 2 peer networking Why client-server computing is not enough always Centralized, distributed and hybrid peer 2 peer systems Wrap up and Conclusions CS 515 Ibrahim Korpeoglu 18
What is Wireless and Mobile Communication? CS 515 Ibrahim Korpeoglu 19
Wireless Communication n n Transmitting voice and data using electromagnetic waves in open space Electromagnetic waves n n Travel at speed of light (c = 3 x 108 m/s) Has a frequency (f) and wavelength (l) § c=fxl n n CS 515 Higher frequency means higher energy photons The higher the energy photon the more penetrating is the radiation Ibrahim Korpeoglu 20
Electromagnetic Spectrum 104 102 100 10 -2 Radio Spectrum 104 106 108 CS 515 Micro wave 1010 1 MHz ==100 m 100 MHz ==1 m 10 GHz ==1 cm 10 -4 1012 10 -6 IR 10 -8 UV 1014 1016 Visible light Ibrahim Korpeoglu 10 -10 10 -12 10 -14 10 -16 X-Rays 1018 1020 Cosmic Rays 1022 < 30 KHz 30 -300 KHz – 3 MHz 3 MHz – 30 MHz – 300 MHz 300 MHz – 3 GHz 3 -30 GHz > 30 GHz 1024 VLF LF MF HF VHF UHF SHF EHF 21
Wavelength of Some Technologies n GSM Phones: q q n PCS Phones q q n frequency ~= 1. 8 Ghz wavelength ~= 17. 5 cm Bluetooth: q q CS 515 frequency ~= 900 Mhz wavelength ~= 33 cm frequency ~= 2. 4 Gz wavelength ~= 12. 5 cm Ibrahim Korpeoglu 22
Frequency Carries/Channels q The information from sender to receiver is carrier over a well defined frequency band. n q q CS 515 This is called a channel Each channel has a fixed frequency bandwidth (in KHz) and Capacity (bit-rate) Different frequency bands (channels) can be used to transmit information in parallel and independently. Ibrahim Korpeoglu 23
Example q q q Assume a spectrum of 90 KHz is allocated over a base frequency b for communication between stations A and B Assume each channel occupies 30 KHz. There are 3 channels Each channel is simplex (Transmission occurs in one way) For full duplex communication: § Use two different channels (front and reverse channels) § Use time division in a channel Channel 1 (b - b+30) Station A Channel 2 (b+30 - b+60) Station B Channel 3 (b+60 - b+90) CS 515 Ibrahim Korpeoglu 24
Homework 1 n Read and digest the following papers! q q M. Weiser, The Computer for the Twenty-First Century, Scientific American, Vol. 265, No. 3, (September 1991), pp. 94 -104. D. Cox, Wireless Personal Communications: What is It? , IEEE Personal Communications Magazine, (April 1995), pp. 20 -35. n CS 515 These papers are on the course webpage! Ibrahim Korpeoglu 25
Simplex Communication n Normally, on a channel, a station can transmit only in one way. n n This is called simplex transmision To enable two-way communication (called full -duplex communication) n n CS 515 We can use Frequency Division Multiplexing We can use Time Division Multiplexing Ibrahim Korpeoglu 26
Duplex Communication - FDD n FDD: Frequency Division Duplex Mobile Terminal M Forward Channel Reverse Channel Base Station B Forward Channel and Reverse Channel use different frequency bands CS 515 Ibrahim Korpeoglu 27
Duplex Communication - TDD n TDD: Time Division Duplex Mobile Terminal M M B M B Base Station B A singe frequency channel is used. The channel is divided into time slots. Mobile station and base station transmits on the time slots alternately. CS 515 Ibrahim Korpeoglu 28
Example - Frequency Spectrum Allocation in U. S. Cellular Radio Service Reverse Channel 991 992 … 1023 1 2 Forward Channel … 799 991 992 824 -849 MHz … 1023 1 2 … 799 869 -894 MHz Channel Number Center Frequency (MHz) Reverse Channel 1 <=N <= 799 991 <= N <= 1023 0. 030 N + 825. 0 0. 030(N-1023) + 825. 0 Forward Channel 1 <=N <= 799 0. 030 N + 870. 0 991 <= N <= 1023 0. 030(N-1023) + 870. 0 (Channels 800 -990 are unused) Channel bandwidth is 45 MHz CS 515 Ibrahim Korpeoglu 29
What is Mobility n Initially Internet and Telephone Networks is designed assuming the user terminals are static n n n No change of location during a call/connection A user terminals accesses the network always from a fixed location Mobility and portability q q CS 515 Portability means changing point of attachment to the network offline Mobility means changing point of attachment to the network online Ibrahim Korpeoglu 30
Degrees of Mobility n Walking Users n n Low speed Small roaming area Usually uses high-bandwith/low-latency access Vehicles n n CS 515 High speeds Large roaming area Usually uses low-bandwidth/high-latency access Uses sophisticated terminal equipment (cell phones) Ibrahim Korpeoglu 31
The Need for Wireless/Mobile Networking n Demand for Ubiquitous Computing q Anywhere, anytime computing and communication n q Pushing the computers more into background n n q Focus on the task and life, not on the computer Use computers seamlessly to help you and to make your life more easier. Computers should be location aware n CS 515 You don’t have to go to the lab to check your email Adapt to the current location, discover services Ibrahim Korpeoglu 32
Some Example Applications of Ubiquitous Computing n n You walk into your office and your computer automatically authenticates you through your active badge and logs you into the Unix system You go to a foreign building and your PDA automatically discovers the closest public printer where you can print your schedule and give to your friend CS 515 Ibrahim Korpeoglu 33
More Examples n You walk into a Conference room or a shopping Mall with your PDA and your PDA is smart enough to collect and filter the public profiles of other people that are passing nearby q n The cows in a village are equipped with GPS and GPRS devices and they are monitored from a central location on a digital map. q n Of course other people should also have smart PDAs. No need for a person to guide and feed them You can find countless examples CS 515 Ibrahim Korpeoglu 34
How to realize Ubiquitous Computing n Small and different size computing and communication devices q q n A communication network to support this q q q n Tabs, pads, boards PDAs, Handhelds, Laptops, Cell-phones Anywhere, anytime access Seamless, wireless and mobile access Need for Personal Communication Services (PCS) Ubiquitous Applications q CS 515 New software Ibrahim Korpeoglu 35
What is PCS Personal Communication Services CS 515 Ibrahim Korpeoglu 36
What is PCS n Personal Communication Services q q q n A wide variety of network services that includes wireless access and personal mobility services Provided through a small terminal Enables communication at any time, at any place, and in any form. The market for such services is tremendously big q CS 515 Think of cell-phone market Ibrahim Korpeoglu 37
Several PCS systems n High-tier Systems q GSM: Global System for Mobile Communications n q IS-136 n n q q USA digital cellular mobile telephony system TDMA based multiple access Personal Digital Cellular IS-95 cdma. One System n CS 515 The mobile telephony system that we are using CDMA based multiple access Ibrahim Korpeoglu 38
Several PCS systems n Low-tier systems q Residential, business and public cordless access applications and systems n n CS 515 Cordless Telephone 2 (CT 2) Digital Enhanced Cordless Telephone (DECT) Personal Access Communication Systems (PACS) Personal Handy Telephone System (PHS) Ibrahim Korpeoglu 39
Several PCS systems n Wideband wireless systems q For Internet access and multimedia transfer n n n CS 515 Cdma 2000 W-CDMA, proposed by Europe SCDMA, proposed by Chine/Europe Ibrahim Korpeoglu 40
Several PCS systems n Other PCS Systems q Special data systems n n n q q Paging Systems Mobile Satellite Systems n q CS 515 CDPD: Cellular Digital Packet Data RAM Mobile Data Advanced Radio Data Information System (ARDIS) LEO, MEO, HEO satellites for data/voice ISM band systems: Bluetooth, 802. 11, etc. Ibrahim Korpeoglu 41
PCS Problems n How to integrate mobile and wireless users to the Public Switched Telephone Network (PSTN) (Voice Network) n n How to integrate mobile and wireless users to the Internet (Data Network) n n Cellular mobile telephony system Mobile IP, DHCP, Cellular IP How to integrate all of them together and also add multimedia services (3 G Systems) CS 515 Ibrahim Korpeoglu 42
Looking to PCS from different Angles PSTN (Telephone Network) Internet Wireless Access Mobile Users -Cell phone users -Cordless phone users Telecom People View CS 515 Ibrahim Korpeoglu Mobile Users -Laptop users -Pocket PC users -Mobile IP, DHCP enabled computers Data Networking People View 43
What does this course cover? n This course will cover the problems/solutions in the telecommunication domain and also in the data networking domain n n Mobile IP (data) TCP over Wireless (data) GSM, GPRS, CDMA (telecom) We will also cover some fundamental problems/solutions for wireless access n n n CS 515 Wireless channel characteristics Recovering from errors Wireless media access Ibrahim Korpeoglu 44
Telecom and Data Networking Telecom Interest - Voice Transmission - Frequency Reuse - Handoff Management -Location Tracking -Roaming -Qo. S -GSM, CDMA, Cordless Phones, -GPRS, EDGE CS 515 Data Networking Interest -Radio Propagation -Link Characteristics -Error Models -Wireless Medium Access (MAC) - Error Control Ibrahim Korpeoglu -Data Transmission -Mobile IP (integrating mobile hosts to internet) -Ad-hoc Networks -TCP over Wireless -Service Discovery 45
Very Basic Cellular/PCS Architecture Mobility Database Public Switched Telephone Network Base Station Controller Mobile Switching Center (MSC) Radio Network Base Station (BS) CS 515 Ibrahim Korpeoglu Mobile Station 46
Wireless System Definitions q Mobile Station q q Base station q CS 515 A station in the cellular radio service intended for use while in motion at unspecified locations. They can be either handheld personal units (portables) or installed on vehicles (mobiles) A fixed station in a mobile radio system used for radio communication with the mobile stations. Base stations are located at the center or edge of a coverage region. They consists of radio channels and transmitter and receiver antennas mounted on top of a tower. Ibrahim Korpeoglu 47
Wireless System Definitions q Mobile Switching Center q q Subscriber q q A user who pays subscription charges for using a mobile communication system Transceiver q CS 515 Switching center which coordinates the routing of calls in a large service area. In a cellular radio system, the MSC connections the cellular base stations and the mobiles to the PSTN (telephone network). It is also called Mobile Telephone Switching Office (MTSO) A device capable of simultaneously transmitting and receiving radio signals Ibrahim Korpeoglu 48
Wireless System Definitions q Control Channel q q Forward Channel q q Radio channel used for transmission of information from the base station to the mobile Reverse Channel q CS 515 Radio channel used for transmission of call setup, call request, call initiation and other beacon and control purposes. Radio channel used for transmission of information from mobile to base station Ibrahim Korpeoglu 49
Wireless System Definitions q Simplex Systems q q Half Duplex Systems q q Communication Systems which allow two-way communication by using the same radio channel for both transmission and reception. At any given time, the user can either transmit or receive information. Full Duplex Systems q CS 515 Communication systems which provide only one-way communication Communication systems which allow simultaneous two-way communication. Transmission and reception is typically on two different channels (FDD). Ibrahim Korpeoglu 50
Wireless System Definitions q Handoff q q Roamer q q A mobile station which operates in a service area (market) other than that from which service has been subscribed. Page q CS 515 The process of transferring a mobile station from one channel or base station to an other. A brief message which is broadcast over the entire service area, usually in simulcast fashion by many base stations at the same time. Ibrahim Korpeoglu 51
PCS Systems Classification n n n Cordless Telephones Cellular Telephony (High-tier) Wide Area Wireless Data Systems (High-tier) High Speed Local and Personal Area Networks Paging Messaging Systems Satellite Based Mobile Systems 3 G Systems CS 515 Ibrahim Korpeoglu 52
Major Mobile Radio Standards USA Standard Type Year Intro Multiple Access Frequency Band (MHz) Modulation Channel BW (KHz) AMPS Cellular 1983 FDMA 824 -894 FM 30 USDC Cellular 1991 TDMA 824 -894 DQPSK 30 CDPD Cellular 1993 FH/Packet 824 -894 GMSK 30 IS-95 Cellular/PCS 1993 CDMA 824 -894 1800 -2000 QPSK/BPSK 1250 FLEX Paging 1993 Simplex Several 4 -FSK 15 DCS-1900 (GSM) PCS 1994 TDMA 1850 -1990 GMSK 200 PACS Cordless/PCS 1994 TDMA/FDMA 1850 -1990 DQPSK 300 CS 515 Ibrahim Korpeoglu 53
Major Mobile Radio Standards Europe Standard Type Year Intro Multiple Access Frequency Band (MHz) Modulation Channel BW (KHz) ETACS Cellular 1985 FDMA 900 FM 25 NMT-900 Cellular 1986 FDMA 890 -960 FM 12. 5 GSM Cellular/PCS 1990 TDMA 890 -960 GMSK 200 KHz C-450 Cellular 1985 FDMA 450 -465 FM 20 -10 ERMES Paging 1993 FDMA 4 Several 4 -FSK 25 CT 2 Cordless 1989 FDMA 864 -868 GFSK 100 DECT Cordless 1993 TDMA 1880 -1900 GFSK 1728 DCS-1800 Cordless/PCS 1993 TDMA 1710 -1880 GMSK 200 CS 515 Ibrahim Korpeoglu 54
Cordless Telephones Cordless Phone CS 515 Base unit Ibrahim Korpeoglu PSTN Telephone Network 55
Cordless Telephones n Characterized by q q q n n Low mobility (in terms of range and speed) Low power consumption Two-way tetherless (wireless) voice communication High circuit quality Low cost equipment, small form factor and long talk-time No handoffs between base units Appeared as analog devices Digital devices appeared later with CT 2, DECT standards in Europe and ISM band technologies in USA CS 515 Ibrahim Korpeoglu 56
Cordless Telephones n Usage q q n At homes At public places where cordless phone base units are available Design Choices q q Few users per MHz Few users per base unit n q q CS 515 Many base units are connected to only one handset Large number of base units per usage area Short transmission range Ibrahim Korpeoglu 57
Cordless Phone n Some more features q q q 32 Kb/s adaptive differential pulse code modulation (ADPCM) digital speech encoding Tx power <= 10 m. W Low-complexity radio signal processing q q CS 515 No forward error correction (FEC) or whatsoever. Low transmission delay < 50 ms Simple Frequency Shift Modulation (FSK) Time Division Duplex (TDD) Ibrahim Korpeoglu 58
Cellular Telephony n Characterized by q q q CS 515 High mobility provision Wide-range Two-way tetherless voice communication Handoff and roaming support Integrated with sophisticated public switched telephone network (PSTN) High transmit power requires at the handsets (~2 W) Ibrahim Korpeoglu 59
Cellular Telephony - Architecture CS 515 Ibrahim Korpeoglu 60
Cellular Telephony Systems n Mobile users and handsets q n Base stations q q n Very complex circuitry and design Provides gateway functionality between wireless and wireline links ~1 million dollar Mobile switching centers q CS 515 Connect cellular system to the terrestrial telephone network Ibrahim Korpeoglu 61
World Cellular Subscriber Growth CS 515 Ibrahim Korpeoglu 62
Mobile Systems Market n Ericsson sells half of the mobile base stations n n Nokia has the biggest market in cell-phones n n 1 base station ~ 100 thousand - 1 million dollar 1 cell-phone ~ 100 dollar Nokia has to sell 10, 000 cell-phones to match the revenue Ericsson obtains from selling just one base-station! CS 515 Ibrahim Korpeoglu 63
Cellular Networks n First Generation n n n Second Generation (2 G) n n n Digital Systems Digital Modulation Voice Traffic TDMA/FDD and CDMA/FDD multiple access 2. 5 G n n n Analog Systems Analog Modulation, mostly FM AMPS Voice Traffic FDMA/FDD multiple access Digital Systems Voice + Low-datarate Data Third Generation n CS 515 Digital Voice + High-datarate Data Multimedia Transmission also Ibrahim Korpeoglu 64
2 G Technologies cdma. One (IS-95) GSM, DCS-1900 IS-54/IS-136 PDC Uplink Frequencies (MHz) 824 -849 (Cellular) 1850 -1910 (US PCS) 890 -915 MHz (Eurpe) 1850 -1910 (US PCS) 800 MHz, 1500 Mhz (Japan) 1850 -1910 (US PCS) Downlink Frequencies 869 -894 MHz (US Cellular) 1930 -1990 MHz (US PCS) 935 -960 (Europa) 1930 -1990 (US PCS) 869 -894 MHz (Cellular) 1930 -1990 (US PCS) 800 MHz, 1500 MHz (Japan) Deplexing FDD FDD Multiple Access CDMA TDMA Modulation BPSK with Quadrature Spreading GMSK with BT=0. 3 p/4 DQPSK Carrier Seperation 1. 25 MHz 200 KHz 30 KHz (IS-136) (25 KHz PDC) Channel Data Rate 1. 2288 Mchips/sec 270. 833 Kbps 48. 6 Kbps (IS-136) 42 Kbps (PDC) Voice Channels per carrier 64 8 3 Speech Coding CELP at 13 Kbps EVRC at 8 Kbps RPE-LTP at 13 Kbps VSELP at 7. 95 Kbps CS 515 Ibrahim Korpeoglu 65
2 G and Data n n n 2 G is developed for voice communications You can send data over 2 G channels by using modem Provides adat rates in the order of ~9. 6 Kbps Increased data rates are requires for internet application This requires evolution towards new systems: 2. 5 G CS 515 Ibrahim Korpeoglu 66
2. 5 Technologies n Evolution of TDMA Systems q HSCSD for 2. 5 G GSM q q GPRS for GSM and IS-136 q q Up to 171. 2 Kbps data-rate EDGE for 2. 5 G GSM and IS-136 q n Up to 57. 6 Kbps data-rate Up to 384 Kbps data-rate Evolution of CDMA Systems q IS-95 B q CS 515 Up to 64 Kbps Ibrahim Korpeoglu 67
3 G Systems n Goals q Voice and Data Transmission n q Multi-megabit Internet access n q q Interactive web sessions Voice-activated calls Multimedia Content n CS 515 Simultanous voice and data access Live music Ibrahim Korpeoglu 68
3 G Systems n Evolution of Systems n CDMA sysystem evaolved to CDMA 2000 § § n GSM, IS-136 and PDC evolved to W-CDMA (Wideband CDMA) (also called UMTS) § § § n CS 515 CDMA 2000 -1 x. RTT: Upto 307 Kbps CDMA 2000 -1 x. EV: CDMA 2000 -1 x. EVDO: upto 2. 4 Mbps CDMA 2000 -1 x. EVDV: 144 Kbps datarate Up to 2. 048 Mbps data-rates Future systems 8 Mbps Expected to be fully deployed by 2010 -2015 New spectrum is allocated for these technologies Ibrahim Korpeoglu 69
Interest to 3 G Applications Emails City maps/directions Latest news Authorize/enable payment Banking/trading online Downloading music Shopping/reservation Animated images Chat rooms, forums Interactive games Games for money Western Europe 4. 5 4. 3 4. 0 3. 4 3. 5 3. 1 3. 0 2. 4 2. 3 2. 0 1. 8 Eastern Europe 4. 7 4. 2 4. 4 3. 8 3. 4 3. 1 2. 7 2. 9 2. 2 1. 8 USA 4. 3 4. 2 4. 0 3. 2 2. 9 2. 6 2. 2 2. 4 1. 8 (Means based upon a six-point interest scale, where 6 indicates high interest and 1 indicates low interest. ) CS 515 Ibrahim Korpeoglu 70
Upgrade Paths for 2 G Technologies IS-95 2 G IS-136 PDC GSM 2. 5 G GPRS IS-95 B HSCSD EDGE 3 G cdma 200 -1 x. RTT W-CDMA EDGE cdma 2000 -1 x. EV, DO TD-SCDMA cdma 200 -3 x. RTT CS 515 Ibrahim Korpeoglu 71
GSM Subscriber Growth CS 515 Ibrahim Korpeoglu 72
CDMA Subscriber Growth CS 515 Ibrahim Korpeoglu 73
CDMA 2000 Subscriber Growth CS 515 Ibrahim Korpeoglu 74
GSM and CDMA Coverage Map Worldwide CS 515 Ibrahim Korpeoglu 75
GSM Networks in Turkey Network System GPRS HSCSD Frequency ------------------------------------------------Aria GSM Live (March 2002) no 1800 Aycell GSM no no 1800 Telsim GSM Live (Aug. 2000) no 900 Turkcell GSM Live (March 2001) soon 900 Number of Subscribers (Nov 2001) Turkcell: 6, 800, 900 Telsim: 2, 800, 000 CS 515 Ibrahim Korpeoglu 76
Coverage Map - Turkcell CS 515 Ibrahim Korpeoglu 77
Coverage Map - Telsim CS 515 Ibrahim Korpeoglu 78
Coverage Map - Aria CS 515 Ibrahim Korpeoglu 79
Coverage Map - Aycell CS 515 Ibrahim Korpeoglu 80
Mobile Phone Market Share n 1 st Quarter of 2002 q q q CS 515 Nokia 34. 7% Motorola 15. 5% Samsung 9. 6% Siemens 8. 8% Sony-Ericsson 6. 4% Ibrahim Korpeoglu 81
Some Mobile Statistics – June 2002 n n n n Total Global Mobile Users: 860 m Total Analog Users: 71 m Total US Mobile Users: 137. 5 m Total GSM Users: 669 m Total TDMA Users: 84 m Total European Users: 279 m Global Montly SMSs/User: 36 SMS Sent in 2001: 102. 9 billion CS 515 n n n n GSM Countries on Air: 171 #1 Mobile Country: China #1 GSM Country: China #1 SMS Country: Phillipines #1 Cell Phone Vendor: Nokia #1 Network in Europa: TMobil #1 Network in Japan: Do. Co. Mo #1 Telecom Infrastructure Company: Ericsson Ibrahim Korpeoglu 82
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