INTRODUCTION TO MOBILE COMMUNICATION SYSTEMS by dr Tibor Kolos Széchenyi István University GYÕR
Mobile communications 11...15/10/2010 ESIGELEC_Rouen 2
Course overview Part 1. Introduction to mobile communications Part 2. Cell structure Part 3. The GSM system Part 4. Base Station Subsystem in GSM Part 5. Traffic engineering Part 6. Cell enhancement Part 7. Location services Part 8. (Laboratory work simulation) 11...15/10/2010 ESIGELEC_Rouen 3
Introduction to Mobile Communication Systems Part 1 Introduction by dr Tibor Kolos Széchenyi István University GYÕR
Content of this chapter A Brief History of Radio Communications General aspects of mobile communications The model of mobile communications Signal to transmit The radio interface (air interface) Developing of system architecture (2G >> 2.5G >> 3G) 11...15/10/2010 ESIGELEC_Rouen 5
A Brief History of Radio Communications 11...15/10/2010 ESIGELEC_Rouen 6
Why to speak about history? 1992. Commercial launch of GSM service GSM God has Sent Mobile 100 years evolution???!!! Telecom engineers must know milestones of this developing process!!! 11...15/10/2010 ESIGELEC_Rouen 7
Industrial environment At the end of 19th century: Steam engine Electric motor Metro line in Budapest Telegraph and phone networks Shipping lines to America No communications with ships! Ericsson "Eiffel Tower" Telephone ca. 1885 The American Museum of Radio and Electricity 11...15/10/2010 ESIGELEC_Rouen 8
The beginning.. 1865. Maxwell equations 1880. H.R.Hertz: generation and detecting of electromagnetic wave 1898. Guglielmo Marconi: wireless telegraph to a ship 11...15/10/2010 ESIGELEC_Rouen 9
Guglielmo Marconi. 11...15/10/2010 ESIGELEC_Rouen 10
First steps 1901. Marconi: transatlantic radio telegraph transmission (3,000 km ) 1900. Reginald Fessenden: human voice (AM) 1906. Fessenden: first radio broadcasting (Maryland, 15 miles.) 1907. Marconi: Commercial radio transmission 1915. Bell Telephone Co.: radio transmission from Virginia to France, -Panama, -Hawaii... 11...15/10/2010 ESIGELEC_Rouen 11
Early mobile systems 1921. Detroit police (2MHz, AM, one-way)..development of technology: valves 1932. New York police (two-way radio) 1935. Edwin H. Armstrong: frequency mod. RF bandwidth: 120 khz, speech bandwidth: 3 khz 1939. Motorway police (FM), Connecticut 11...15/10/2010 ESIGELEC_Rouen 12
Military telegraph station 1901 Source: Western Electrician, July 27, 1901, page 51: 11...15/10/2010 ESIGELEC_Rouen 13
Radiotelephony for railroads (1914) Source: Electrical World, May 30, 1914, page 1269: 11...15/10/2010 ESIGELEC_Rouen 14
Military radio (WW I.) Source: Look Ma, no Wires.. 11...15/10/2010 ESIGELEC_Rouen 15
Old receivers. 11...15/10/2010 ESIGELEC_Rouen 16
World War II. Military applications of mobile systems Aim of development: protection against Interference Unauthorised reception Modulation: AM or FM? Results of developments: Handheld FM transceivers (walkie-talkie) First steps to spread spectrum technology (SFH-SS) 11...15/10/2010 ESIGELEC_Rouen 17
Commercial mobile services 1946. After military developments: Increasing demands for civil applications (FM) Frequency bands: 40 MHz and 150 MHz Operation mode: simplex ( push to talk ) PMR: Private/Professional Mobile Radio (dispatch services: police, taxi, ambulance, etc.) PLMR: Public Land Mobile Radio (~100 subscriber/carrier, connected to PSTN) 11...15/10/2010 ESIGELEC_Rouen 18
Increasing of capacity 1950: Spectrum leakage (150 MHz band) Increasing of capacity: decreasing of channel spacing instead of 120 khz: 60 khz, (later 30 or 25 khz) decreasing of interference protection, noise! decreasing of frequency stability, receiver selectivity Introduction of trunk system (FDMA) Frequency reuse (later cellular system) 11...15/10/2010 ESIGELEC_Rouen 19
Car phone systems 1960th: duplex mobile systems MTS, IMTS (Improved Mobile Telephone Service) Large covered area high transmitter output power 1970th: increasing demands for the car phone, ( zero-generation system) The transceiver was built in a car (or in a suitcase) Cell radius:10.. 15 km No handover (it wasn t necessary.) Limited capacity 11...15/10/2010 ESIGELEC_Rouen 20
Portable phone (~ 1970) 11...15/10/2010 ESIGELEC_Rouen 21
First generation systems 1980th: Launch of cellular public mobile phone systems Aim: speech transmission Technology for 1G system: Cellular, FDMA trunking, analogue FM NMT (Nordic Mobile Telephone system) AMPS (Advanced Mobile Phone System) TACS (Total Access Communication System) Radiocomm-2000 C-netz FI USA GB FR GER 11...15/10/2010 ESIGELEC_Rouen 22
Disadvantages of 1G systems System concept and architecture: from 70th No real encryptions on air interface Made for speech transmission Limited data transmission Limited capacity, low spectrum efficiency Incompatible systems No European roaming 11...15/10/2010 ESIGELEC_Rouen 23
Second generation systems (1) Different technologies for 2G in America and in Europe 1982. CEPT* established the GSM workgroup Group Spéciale Mobile, later Global System for Mobile The aim: to outwork a common European standard for the Pan-European public mobile phone system Question to decide: analogue or digital system? *CEPT: European Conference of Postal and Telecommunications Administrations 11...15/10/2010 ESIGELEC_Rouen 24
Second generation systems (2) 1988. Successful trials of the digital system TDMA trunk system (TDMA -FDMA) Enhanced services Speech or data transmission, Encryption Better spectrum efficiency 1992. Commercial 2G service by GSM system 11...15/10/2010 ESIGELEC_Rouen 25
Advantages of 2G systems Better spectrum efficiency Large capacity (900 MHz and 1800MHz band) Digital modulation in the air interface Error correction Good speech and data transmission quality Encryption Protection against fraud Big market low equipment and service prices European roaming today not only in Europe! Base of the future planned systems (2.5G, 3G.) 11...15/10/2010 ESIGELEC_Rouen 26
Disadvantages of 2G systems Designed for speech (and data) transmission Low bit rate (14.4 kbit/s) data transmission Limited content services No global roaming 11...15/10/2010 ESIGELEC_Rouen 27
Systems beyond 2G (today) 2.5 G designed for increased data transmission Up to 384 kbit/s Based on air interface of 2G 3G designed for high speed data transmission Up to 2Mbit/s New air interface, based on CDMA multiple access Global roaming (???...) ( doesn t exists..) 3.5G increased data transmission capability (7,2 14,4 Mbit/s) Modified air interface (HSDPA, HSUPA) 4 G future planned system (up to 100 300 Mbit /s????...) LTE (Long Term Evolution) WiMax (Worldwide Interoperability For Microwave Access) (????) 11...15/10/2010 ESIGELEC_Rouen 28
Useful links to the history http://people.deas.harvard.edu/~jones/cscie129/nu _lectures/lecture7/cellular/cell_hist.html http://people.deas.harvard.edu/~jones/cscie129/nu _lectures/lecture6/marconi/marconi.html http://inventors.about.com/library/inventors/blcell. htm http://www.cellular.co.za/gsmhistory.htm Homework: Find some technical descriptions about Marconi s radio transmitter and receiver! 11...15/10/2010 ESIGELEC_Rouen 29
This is the end of the historical overview! Let see some General aspects of mobile communications 11...15/10/2010 ESIGELEC_Rouen 30
Wireless communications (1) Wireless: transmission by radiated EM waves Fix (Point to point, point to multipoint) Mobile WLAN (IEEE 802.11 2.4 GHz???) Based on computer networks Mobile phone systems (GSM, UMTS..) Based on phone networks Not only phone services!!! WLAN??? Mobile phone Are they competitive or cooperative systems??? 11...15/10/2010 ESIGELEC_Rouen 31
Wireless communications (2) Wireless in telecommunication systems Last kilometres (Mobile phone systems, GSM) Last hundred meters (DECT) Last ten meters (WLAN) Last meters (Bluetooth) Last centimetres (RFID) All above apply radiated electromagnetic waves 11...15/10/2010 ESIGELEC_Rouen 32
Mobile phone systems PRIVATE (DLMN) PUBLIC (PLMN) Police Emergency Railway Taxi Highway patrol Mobile phone limited coverage global coverage 11...15/10/2010 ESIGELEC_Rouen 33
Mobile communications (1) The service provider s approach: Increasing number of customers (>100%!!!) Wide scale of services (voice + data) Mobile communications = business 11...15/10/2010 ESIGELEC_Rouen 34
Mobile communications (2) The customer s approach: As a user of network, wants to have access to any other user anytime anywhere to change any kind of information (speech, picture, text) 11...15/10/2010 ESIGELEC_Rouen 35
Mobile communications (3) Services expected by a customer high quality speech, emergency call + location service SMS, data transmission, Internet browsing, m-commerce, music, video download games (bit rate???) 11...15/10/2010 ESIGELEC_Rouen 36
Mobile communications (4) The system engineer s approach Marketing Service Technology (telecom and production) Ethics and law Environmental protection EMC Health issues Visual environment 11...15/10/2010 ESIGELEC_Rouen 37
Statistics (1) Number of service providers Technology (analogue, digital) Coverage (2G, 2.5G, 3G) (geographical, or % of inhabitants) Number of subscribers (active SIM cards) Penetration (% of population) Growth (during 1 month, or 1 year) 11...15/10/2010 ESIGELEC_Rouen 38
Statistics (2) HUNGARY Mobile phone 31/08/2010 Number of operators: 3 Number of subscribers: 11.82 Millions Penetration: 118,2 % (????) Growth: 99,6 % (1 month) 99,8 % (1 year) source: www.nmhh.hu Homework: collect statistics about French mobile phone operators 11...15/10/2010 ESIGELEC_Rouen 39
Statistics (2) HUNGARY Mobile internet 31/08/2010 Number of operators: Technology: GPRS, UMTS, HSPA Number of subscribers: 1 136 524 3 (T-Mobil, Telenor, Vodafone) Growth: Avarage traffic: Coverage: 157 % (12 month!) 1.35 GByte/subs/month see maps on next pages!!! source: www.nmhh.hu Homework: collect statistics about French mobile phone operators! 11...15/10/2010 ESIGELEC_Rouen 40
Telenor GPRS coverage Indoor Outdoor 11...15/10/2010 ESIGELEC_Rouen 41
Telenor EDGE coverage Indoor Outdoor 11...15/10/2010 ESIGELEC_Rouen 42
Telenor UMTS coverage Indoor Outdoor 11...15/10/2010 ESIGELEC_Rouen 43
Generations of mobile systems by data transmission capability 0G speech transmission only, pure services 1G speech + pure data transmission 2G speech = data transmission (14.4 kbit/s) 2.5G increased data rate (56 384 kbit/s) 3G high data rate (up to 2 Mbit/s) 3.5 G increased high data rate (up to or >14.4 Mbit/s) 4G very high data rate ( > 100 Mbit/s) (?) 11...15/10/2010 ESIGELEC_Rouen 44
Technology beyond 2G (1) 2G GSM 9.6 kbit/s 1 timeslot GSM 14.4 kbit/s 1 timeslot 2.5G HSCSD 28.4.56 kbit/s 2 4 timeslots GPRS up to 100 kbit/s 2 8 timeslots EDGE up to 384 kbit/s new modulation 3G UMTS up to 2 Mbit/s spread spectrum 3.5 G HSDPA/UPA 7,2 (14,4) Mbit/s new modulation 4G LTE and/or WiMax????????? MIMO technology 11...15/10/2010 ESIGELEC_Rouen 45
Technology beyond 2G (2) HSCSD High Speed Circuit Switched Data Maximum 4 x 14.4 kbit /s Software changing in the fix network >> cheep! GPRS General Packet Radio Service Few new hardware + new software in the fix network EDGE Enhanced Digital GSM Evolution Maximum 384 kbit /s >> adaptive bit rate! New hardware on BTS-s >> for extensions only! Generates demands on high bit rate >> 3G 11...15/10/2010 ESIGELEC_Rouen 46
Technology beyond 2G (3) UMTS Universal Mobile Telecommunications System 3G services, maximum 2Mb/s New air interface spread spectrum technology New BTS equipment, High capacity data transmission links in the fix network For extension! HSDPA High-Speed Downlink Packet Access HSUPA High-Speed Uplink Packet Access Based on UMTS hardware New (higher level) modulation, new protocol 11...15/10/2010 ESIGELEC_Rouen 47
Technology beyond 2G (4) LTE Long Term Evolution) WiMax Worldwide Interoperability for Microwave Access Competitive systems 4G services New telecom technology in the air interface (MIMO) 11...15/10/2010 ESIGELEC_Rouen 48
The model of mobile communications 11...15/10/2010 ESIGELEC_Rouen 49
Model of mobile communications (1) Information in Information out Source encoding Source decoding Channel Transmitter encoding Channel Receiver decoding Modulation RF channel Demodulation 11...15/10/2010 ESIGELEC_Rouen 50
Model of mobile communications (2) Information in Information out Source encoding Source decoding Channel encoding interference noise Channel decoding Modulation RF channel Demodulation 11...15/10/2010 ESIGELEC_Rouen 51
Model of mobile communications (3) Source coding Speech coding (compression) Encryption (??) Channel coding Error correction Adding redundancy Interleaving Modulation of RF carrier (spectrum efficiency!!!) Multiple access 11...15/10/2010 ESIGELEC_Rouen 52
Signal processing (1) (old analogue systems) Speech Bandwidth limitation Analogue modulation RF carrier (analogue FM) 11...15/10/2010 ESIGELEC_Rouen 53
Signal processing (2) (digital systems) Speech Picture Data A/D, speech coding (A/D), picture coding Encryption, error coding Digital modulation Modulated RF carrier 11...15/10/2010 ESIGELEC_Rouen 54
Signal to transmit 11...15/10/2010 ESIGELEC_Rouen 55
Signal to transmit (1) Analogue Digital upper limit continuous discrete lower limit 2, 4, 8, 16, 64,..levels 11...15/10/2010 ESIGELEC_Rouen 56
Signal to transmit (2) Human speech Analogue signal Frequency band Dynamics Quality measurement: S/N (obj.).. (subj.) Data Digital signal Bit rate (or symbol rate) Quality: BER ( obj.) 11...15/10/2010 ESIGELEC_Rouen 57
Signal to transmit (3) Bla..bla..bla ANALOGUE TRANSMISSION SYSTEM Bla..bla..bla 11...15/10/2010 ESIGELEC_Rouen 58
Signal to transmit (4) 1 1 0 1 0... DIGITAL TRANSMISSION SYSTEM 1 1 0 1 0... 11...15/10/2010 ESIGELEC_Rouen 59
Signal to transmit (5) 1 1 0 1 0... DIGITAL TRANSMISSION SYSTEM 1 1 0 1 0... Bla..bla..bla A/D 1 1 0 1 0... DIGITAL TRANSMISSION SYSTEM 1 1 0 1 0... D/A Bla..bla..bla analogue digital analogue 11...15/10/2010 ESIGELEC_Rouen 60
The quality Q Q analogue digital??? RF attenuation RF attenuation 11...15/10/2010 ESIGELEC_Rouen 61
Bit rates for speech transmission ISDN: 64 kbit/s (waveform coding) GSM: 13 kbit/s (full rate compressed, hibrid vocoder) GSM: 6.5 kbit/s (half rate compressed, hibrid vocoder) TETRA: 4.8 kbit/s Quality! 11...15/10/2010 ESIGELEC_Rouen 62
Bit rates for data transmission Internet browsing, download Videoconferencing Video telephony Teleshopping Images/sound files Financial services Information services E-mail Voice???? Bit rate 10 kbps 100 kbps 1Mbps 2Mbps 11...15/10/2010 ESIGELEC_Rouen 63
The radio interface (air interface) 11...15/10/2010 ESIGELEC_Rouen 64
Frequency spectrum From 0 Hz up to Specification: In frequency (Hz) In wavelength (m) Radio frequency band: 9 khz..300 GHz Be careful: 9 khz frequency Sound (produced by loudspeaker) EM wave (produced by LC resonant circuit) 11...15/10/2010 ESIGELEC_Rouen 65
Electromagnetic Spectrum Radio frequences 11...15/10/2010 ESIGELEC_Rouen 66 Source: http://en.wikipedia.org/wiki/electromagnetic_spectrum
Properties of electromagnetic waves Frequency Wavelength Properties Applications Antenna 10 khz 30 km under water submarine H loop 100 khz 3 km into the earth 70 khz clock H ferrite 1MHz 300 m surface AM broadcast H ferrite 10 MHz 30 m reflections (ionosphera) AM broadcast H ferrite 30 MHz 10 m reflections (ionosphera) 27 MHz CB E wire monop 100 MHz 3 m direct FM broadcast E dipole 300 MHz 1 m direct Private mobile E monopole 1 GHz 30 cm reflections (buildings) GSM E monopole 3 GHz 10 cm direct radar, telecom Parabolic 10 GHz 3 cm direct, rain attenuation radar, telecom Parabolic 30 GHz 10 mm direct, rain attenuation telecom Parabolic 100 GHz 3 mm direct, rain attenuation?????? array 11...15/10/2010 ESIGELEC_Rouen 67
Spectrum management International level ITU (International Telecommunication Union) National level National frequency management authorities National frequency usage table International cooperation Company level Mobile service providers Army 11...15/10/2010 ESIGELEC_Rouen 68
Frequency allocation (US) Visit the homepage: http://en.wikipedia.org/wiki/frequency_allocation 11...15/10/2010 ESIGELEC_Rouen 69
Choose a proper carrier! (1)( Frequency bands: licensed and license free Licensed bands Near all bands Supervisor: National Telecommunication Authority Administrative protection against interfering signals Limits for effective antenna height and ERP The user have to pay for the usage of spectrum 11...15/10/2010 ESIGELEC_Rouen 70
Choose a proper carrier! (2)( License free bands 27 MHz CB radio, 433.9 MHz SRD 2.4 GHz and 5 GHz ISM bands, (Industrial, Scientific and Medical) No license, no payment, no protection! Hard limitations for equipment specifications! TX: output power limit, spurious signal limit RX: spurious signal limit, blocking EN standards for conformity and EMC measurements! CE Spread Spectrum technology to avoid interference 5 GHz WLAN: DFS against radar interference (Dynamic Frequency Selection) 11...15/10/2010 ESIGELEC_Rouen 71
PSTN ISDN PDN System architecture of mobile networks Radio interface Abi s A FIX PART OF MOBILE COMMUNICATION SYSTEM MS BSS SMSS OMSS 11...15/10/2010 ESIGELEC_Rouen 72
Functions of radio interface Speech coding (compression) Encryption Error correction Generation of RF carrier Modulation Multiple access 11...15/10/2010 ESIGELEC_Rouen 73
Radio interface: RF generation Frequency bands for public mobile phone networks 450MHz band: NMT (analogue) 900 MHz band: NMT (analogue) 900 MHz band: GSM (digital) 890-915 and 935-960 MHz (124 carriers, Standard GSM) 880-915 and 925-960 MHz (174 carriers, Extended GSM) 1800 MHz band: GSM (digital) 1710-1785 and 1805-1880 MHz 1900 MHz band: GSM in America 2000 MHz band: UMTS (spread spectrum) 11...15/10/2010 ESIGELEC_Rouen 74
Radio interface: modulation Analogue frequency modulation (FM) 1G Digital GMSK modulation 2G Digital 8PSK phase modulation 2.5G Spread spectrum technology 3G Direct sequence spread spectrum (DS-SS) Frequency hopping (FH-SS) OFDM system 11...15/10/2010 ESIGELEC_Rouen 75
Radio interface: multiple access BTS 11...15/10/2010 ESIGELEC_Rouen 76 Abis
Multiple access technologies: FDMA FDMA Frequency Division Multiple Access 11...15/10/2010 ESIGELEC_Rouen 77
Multiple access technologies: TDMA TDMA Time Division Multiple Access 11...15/10/2010 ESIGELEC_Rouen 78
Compare FDMA and TDMA! FDMA TDMA Frequency Division Multiple Access Time Division Multiple Access 11...15/10/2010 ESIGELEC_Rouen 79
Multiple access technologies: TDMA - FDMA 11...15/10/2010 ESIGELEC_Rouen 80
Multiple access technologies: CDMA Code Division Multiple Access 11...15/10/2010 ESIGELEC_Rouen 81
Solutions for radio interface 1G: 2G: 2.5G: 2.5G: FM analogue modulation, FDMA NMT 450, AMPS, C-netz. GMSK digital modulation, TDMA-FDMA GSM GMSK digital modulation, TDMA-FDMA GSM-GPRS 8PSK digital modulation, TDMA-FDMA GSM-EDGE 3G: Spread spectrum techn. W-CDMA UMTS cdma2000 is a 2G system! 11...15/10/2010 ESIGELEC_Rouen 82
Developing of system architecture 2G >> 2.5G >> 3G 11...15/10/2010 ESIGELEC_Rouen 83
Repetition! Radio interface System architecture Abi s A PSTN ISDN PDN FIX PART OF MOBILE COMMUNICATION SYSTEM MS BSS SMSS OMSS 11...15/10/2010 ESIGELEC_Rouen 84
Um GSM system architecture (1) Abis A PSTN ISDN PDN MS BSS SMSS OMSS 11...15/10/2010 ESIGELEC_Rouen 85
Um GSM system architecture (2) Abis A PSTN ISDN PDN BSC BSC EIR MSC GCR VLR HLR AUC MS BTS-s. BSC BSS MSC VLR SMSS OMSS 11...15/10/2010 ESIGELEC_Rouen 86
Um GPRS system architecture Abis A EIR VLR PSTN ISDN PDN BSC BSC MSC GCR HLR AUC BTS-s MS BSS. BSC OMSS SGSN MSC Backbone GGSN VLR SMSS 11...15/10/2010 ESIGELEC_Rouen 87 IP
Um 3G system architecture (1) BSS Abis A EIR VLR PSTN ISDN PDN BSC MSC HLR BSC GCR AUC. RNC SGSN MSC VLR MS Node B IP Backbone OMSS GGSN SMSS 11...15/10/2010 ESIGELEC_Rouen 88 IP
Um 3G system architecture (2) Abis A PSTN ISDN PDN BSS EIR VLR BSC MSC HLR BSC GCR AUC. RNC SGSN MSC VLR MS Node B UTRAN Iub OMSS IP Backbone GGSN SMSS 11...15/10/2010 ESIGELEC_Rouen 89 IP
List of Acronyms BSC BSS EIR GGSN HLR MSC RNC SGSN UMTS UTRAN VLR Base station controller Base station system Equipment identity register Gateway GPRS support node Home location register Mobile services switching centre Radio network controller Serving GPRS support node Universal Mobile Telecommunications Systems Universal Terrestrial Radio Access Network Visitor location register 11...15/10/2010 ESIGELEC_Rouen 90
Contact Lecturer: dr Tibor KOLOS Szechenyi Istvan University Gyor HUNGARY Web: http://www.sze.hu http://rf.sze.hu E-mail: kolos@sze.hu 11...15/10/2010 ESIGELEC_Rouen 91
! THANKS FOR THE ATTENTION! 11...15/10/2010 ESIGELEC_Rouen 92