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Cell Phone Technology: GSM vs. CDMA. How networking affects cell phone technology. . What is GSM?. GSM stands for G lobal S ystem for M obile Communications Is a cellular network that mobile phones can connect to. Is the standard in cell phone network systems
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Cell Phone Technology: GSM vs. CDMA How networking affects cell phone technology. David Lloyd & Kachi Nwogu
What is GSM? • GSM stands for Global System for Mobile Communications • Is a cellular network that mobile phones can connect to. • Is the standard in cell phone network systems • Was introduced to the world in 1982 David Lloyd & Kachi Nwogu
Where is GSM used? • Used in over 170 countries • GSM is used in over ¾ of the world’s wireless networks • Used by 1.5 billion customers globally • Has over 3 billion connections David Lloyd & Kachi Nwogu
GSM Technical Components of Mobile Communication David Lloyd & Kachi Nwogu
The Goals of GSM • International roaming • Low-cost mobile sets • Compatibility with ISDN and other telephone company services • Support for new services and technology David Lloyd & Kachi Nwogu
GSM Cell Structure • Neighboring cells cannot share channels David Lloyd & Kachi Nwogu
Types of cells • Macro cells(3 to 35 km) • Microcells(0,1 to 1 km) • Pico cells(0,01 to 1km) • Nanocells(1m to 10m) David Lloyd & Kachi Nwogu
GSM’s impact • By good communication provided by the GSM network it creates: • More jobs directly and indirectly • A safer community • A boost in the economy because of better business • Overall a improved quality of life. David Lloyd & Kachi Nwogu
What is CDMA? • CDMA stands for Code Division Multiple Access • Is a cellular network that mobile phones can connect to. • is a channel access method used by various radio communication technologies • Originally created in WWII to transmit over multiple frequencies rather then just 1. • Encodes data with a special code • A proprietary standard designed by Qualcomm David Lloyd & Kachi Nwogu
Who uses CDMA? • Is used by GPS (Global positioning systems) • Primarily used in the U.S. and portions of Asia • Newly introduced in sub-saharan African market David Lloyd & Kachi Nwogu
CDMA – Problems/Benefits • Problems: • Requires fast and accurate power control • Tight synchronization is required • Benefits: • Can reuse frequencies every cell • Does not rely on orthogonal frequency and time slots that are compromised by neighboring cells David Lloyd & Kachi Nwogu
Summary of CDMA • Allows efficient use of spectrum • Code division with same time and frequency • Strong against interference • Graceful degradation as traffic increases David Lloyd & Kachi Nwogu
Cell phone telephony and networking • Bandwidth allocation • Speed • Functionality • Base station subsystem • Core csn [voice and text] • Packet switched network [mobile data] • Pstn [connects subscribers to public telephony] • internetworking David Lloyd & Kachi Nwogu
GSM or CDMA? • US GSM carriers • T-Mobile, AT&T Wireless • US CDMA carriers • Sprint, Virgin Mobile and Verizon Wireless • CDMA – better bandwidth handling • CDMA – soft hand off • GSM - more widely used and has better coverage's then CDMA • CDMA is known to have better call quality David Lloyd & Kachi Nwogu
CDMA or GSM ? • CDMA – more cost effective • But ineffective handoff can be expensive • Bandwidth overload can be expensive • GSM – no frequency conflict or interference David Lloyd & Kachi Nwogu
Quo Vadis ? • Network hopping • Bandwidth wars • Morphing • Tele-camera-rfid-gps marriage [point+find] • The IMS (IP Multimedia Subsystem) • What's next? • Questions. Comments. Concerns. David Lloyd & Kachi Nwogu