Intro To Gsm Wh080917
- 1. Wade Hwang Introduction to GSM system
- 2. 06/10/09 Introduction to GSM system, Wade Hwang Outline Migration of GSM system History of public wireless communication History of GSM system Working principle of GSM system Concept of GSM system Main components Network structure Important interfaces Features of GSM system
- 3. 06/10/09 Introduction to GSM system, Wade Hwang History of public wireless communication
- 4. 06/10/09 Introduction to GSM system, Wade Hwang 1997 500 1000 2000 2003 1500 400 2005 2000 2500 2007 3000 Subscribers (Millions) UMTS 100 Million History of public wireless communication 1000 3000 Global mobile-phone subscribers hit 2B (Oct 05)
- 5. 06/10/09 Introduction to GSM system, Wade Hwang History of GSM system Group Special Mobile (GSM) is formed by the Confederation of European Posts and Telecommunications (CEPT) to design a pan-European mobile technology. Trials of different digital radio transmission schemes and different speech codecs in several countries, with comparative evaluation by CEPT GSM in Paris. Basic parameters of the GSM standard agreed in February. TDMA, RPE—LTP, GMSK Completion of first set of detailed GSM specifications for infrastructure tendering purposes. first GSM call made by Radiolinja in Finland. Group Special Mobile defines the GSM standard as the internationally accepted digital cellular telephony standard. 92 First international roaming agreement signed between Telecom Finland and Vodafone (UK). First SMS sent. 02 95% of nations worldwide have GSM networks. 06 GSM SURPASSES TWO BILLION CUSTOMERS. 03 First EDGE networks go live. First commercial GPRS services launched. GSM surpasses 3 Billion connections 1982 1984 1985 1986 1987 1988 1989 1991 1992 1993 1994 2000 2001 2002 2003 2004 2006 2007 2008
- 6. 06/10/09 Introduction to GSM system, Wade Hwang Outline Migration of GSM system History of public wireless communication History of GSM system Working principle of GSM system Concept of GSM system Main components Network structure Important interfaces Features of GSM system
- 7. 06/10/09 Introduction to GSM system, Wade Hwang Concept of GSM system GSM operation section (worldwide) PLMN operation section (one or more in a country) MSC operation section (one district controlled by a MSC) LAI (Locating & paging district) Cell (a specific area covered by a BTS)
- 8. 06/10/09 Introduction to GSM system, Wade Hwang LAI ( L ocation A rea I dentity) Each location area of a public land mobile network (PLMN) has its own unique identifier which is known as Location Area Identity (LAI). PLMN ( P ublic L and M obile N etwork) A public land mobile network (PLMN) is a network that is established and operated by an administration or by a recognized operating agency (ROA) for the specific purpose of providing land mobile telecommunications services to the public. For example, in china, MNC (Mobile Network Code) of China Mobile’s GSM network is ‘00’, while China Unicom’s is ‘01’. GSM operation section Worldwide wireless communication network. MSC operation section One district controlled by a MSC CELL A specific area covered by a BTS Concept of GSM system
- 9. 06/10/09 Introduction to GSM system, Wade Hwang Main components NSS ( N etwork S witching S ubsystem) It carries out switching functions and manages the communications between mobile phones and the Public Switched Telephone Network. BSS ( B ase S tation S ubsystem) Responsible for handling traffic and signaling between a mobile phone and the network switching subsystem. OMC ( O perations and M aintenance C enter) The functional entity from which the network operator monitors and controls the system. MS ( M obile S tation) MS refers to the Mobile Phone. i.e. the handset held by the users in the mobile network.
- 10. 06/10/09 Introduction to GSM system, Wade Hwang Network structure and main interfaces
- 11. 06/10/09 Introduction to GSM system, Wade Hwang Important interfaces Um - The air interface between the MS (Mobile Station) and the BTS. Call control, measurement reporting, Handover, Power control, Authentication, Authorization, Location Update and so on. Abis - The interface between the BTS and BSC. BTS supervision and telecom signaling, and carries synchronization from the BSC to the BTS and MS. A - The interface between the BSC and Mobile Switching Center. Carrying Traffic channels Ater - The interface between the BSC and Transcoder. Gb - Connects the BSS to the Serving GPRS Support Node (SGSN) in the GPRS Core Network.
- 12. 06/10/09 Introduction to GSM system, Wade Hwang Outline Migration of GSM system History of public wireless communication History of GSM system Working principle of GSM system Concept of GSM system Main components Network structure Important interfaces Features of GSM system
- 13. 06/10/09 Introduction to GSM system, Wade Hwang Features of GSM system Spectrum efficiency Improved spectrum efficiency due to new technologies utilized such as efficient modulator and demodulator, channel coding, Interleaving, equalization and Vocoder System capacity 3-5 times higher than TACS due to TDMA, half-speed Vocoder and other technologies adopted. Voice quality Same voice quality in the coverage where the signal strength is higher than threshold. Open interfaces Not only open air interface but also open interfaces between system components, enables flexibility. Security Authentication, encryption and TMSI (temporary mobile subscriber identity). Roaming SIM (subscriber identity module) and IMSI.
- 14. 06/10/09 Introduction to GSM system, Wade Hwang Q&A Thank you