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Mobile Phones. Done By : Saed Fathi 1998 / 2104 Ramy Ghaboun 2002 / 1895 3. Abd Al_Rhman Tabeel 2001 / 0306 Supervision : Dr.eng. Basil Hammad. Contents. Introduction Cells Multiple Access Mobile Generations. Mobile Network. Introduction. What is a mobile phone ?
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Mobile Phones • Done By : • Saed Fathi 1998 / 2104 • Ramy Ghaboun 2002 / 1895 • 3. Abd Al_Rhman Tabeel 2001 / 0306 • Supervision : • Dr.eng. Basil Hammad
Contents • Introduction • Cells • Multiple Access • Mobile Generations
MobileNetwork Introduction • What is a mobile phone ? It is a device for sending voice and data through radio signals to the mobile and telephone network. • What is BTS ? Base Transceiver (transmitter and receiver) Station.
ACTUAL COVERAGE AREA OF CELL 1 Cells • Cell • Cluster • Hexagon shape
Space Division Multiple Access (SDMA) MANY CELLS CAN SHARE SAME FREQUENCIES IF SEPARATED IN SPACE • Why Wireless? PATTERN CAN BE REPLICATED OVER THE ENTIRE EARTH 200 FREQUENCIES IN ONE CELL TOTAL NUMBER OFFREQUENCIES = 1400 WORLDWIDE
k1 k2 k3 k4 k5 k6 c f t Frequency Division Multiplexing (FDMA)
c FREQUENCY BAND f t Time Division Multiplexing (TDMA)
c f t Combination Between FDMA &TDMA
c f t Code Division Multiplexing (CDMA)
First Generation • Single cell systems - Push-to-talk Phones. - Dual-channel Phones. • Cellular systems • AMPS. • TACS. • AMPS & TACS.
DATA RATE: 9.6 Kbps nd 2 . Generation GSM Architecture CELL TRANSMITTER & RECEIVER INTERFACE TO LANDTELEPHONE NETWORKS HIERARCHY OF CELLS PHONE SIM: IDENTIFIES A SUBSCRIBER
Cell Handover AS PHONE MOVES FROM CELL “A” TO CELL “B”: • CELL “A” MUST HAND THE CALL OVER TO “B” • PHONE MUST CHANGE FREQUENCIES • CELL “A” MUST STOP TRANSMITTING Minimum performance contour A x y B z Handover threshold contour
2 Subscriber Services : nd There are two basic types of services offered through GSM: Telephon (also referred to as teleservices) and data (also referred to as bearer services). • Short Message Services. • Cell Broadcast. • Call Forwarding. • Call Hold. • Call Waiting. • Multiparty Services. • Closed User Groups (CUGS).
UMTS -Main Characteristics • The main Features of 3G systems, known collectively as IMT–2000, are single family of compatible standards • Main characteristics • UMTS supports the virtual home environment (VHE) concept
UMTS Architecture • The UMTS architecture is split into: • core (switching) network • UMTS Terrestrial Radio Access Network (UTRAN) • User Equipment
Summary • First • Analog, circuit-switched (AMPS) • Second • Digital, circuit-switched (GSM) • 10 Kbps • 2.5 • Digital, packet-switched, TDMA (GPRS)40-400 Kbps • Third • Digital, packet-switched, wideband CDMA (UMTS)0.4 – 2 Mbps • Fourth • Data rate 100 Mbps.
A Q &
DATA 1 0 1 “CODE” 0 1 0 1 0 0 1 0 0 0 1 0 1 1 0 0 1 1 DATA CODE 1 0 1 0 1 1 1 0 0 0 1 0 0 0 1 1 0 0 +1 ACTUAL SIGNAL -1 Code Division
DATA B 1 0 0 “CODE” B 0 0 0 1 1 0 1 0 1 0 0 0 0 1 0 1 1 1 DATA CODE 1 1 1 0 0 1 1 0 1 0 0 0 0 1 0 1 1 1 +1 ACTUAL SIGNAL B -1 Code Division
+1 ACTUAL SIGNAL B -1 +1 ACTUAL SIGNAL A -1 Two CDMA Signals +2 ACTUAL SIGNAL A+B -2
+2 ACTUAL SIGNAL A+B -2 “CODE” A 0 1 0 1 0 0 1 0 0 0 1 0 1 1 0 0 1 1 Recovering Data A From A+B +1 -1 +2 -(A+B) * CODE A -2 0 INTEGRAL 1 1