Evolution of Wireless Mobile Communications (I)2011. 4.25HyungHyung-Jin Choi Sungkyunkwan doc

Evolution of Wireless Mobile Communications (I)Evolution of Wireless Mobile Communications (I) 2011. 4.25 2011. 4.25 HyungHyung Jin Jin ChoiChoi SungkyunkwanSungkyunkwan UniversityUniversity Evolution of Wireless Mobile CommunicationsEvolution of Wireless Mobile Communications [...]... system Presently the responsibility of GSM standardization resides with special mobile group under ETSI(European telecommunication Standards Institute) Full set of specifications phase-I became available in 1990 Under ETSI, GSM is named as “ Global System for Mobile communication “ Architecture of GSM SIM – Subscriber Identity Module ME – Mobile Equipment UM – User Mobile Frequency BTS – Base Transceiver... the most important concepts to any cellular telephone system is that of “multiple access” CDMA - a large number of users share a common pool of radio channel bandwidth and any user can gain access to a pool of channels (one common frequency band for all users), thus cell capacity (# of users in a cell) is limited only by interference (soft capacity) An idea derived from military & developed by Qualcomm,... networks in Europe operate in the 2100 MHz frequency band One of the key features of GSM is the Subscriber Identity Module Card GSM additionally provides Integrated voice mail High speed data and fax Paging and Short Message Services (SMS) GSM History Developed by Group Spéciale Mobile (founded 1982) which was an initiative of CEPT (Conference of European Post and Telecommunication) Developed to replace... was defined by the RCR (later became ARIB) of Japan in April 1991 NTT DoCoMo launched its Digital mobile service in March 1993 PDC uses 25 kHz carrier, pi/4-DQPSK modulation with 3-timeslot 11.2 kbit/s (full-rate) or 6-timeslot 5.6 kbit/s (half-rate) voice codecs Personal Communication Service (PCS) PCS is the name for the 1900 MHz radio band used for digital mobile phone services in Canada, Mexico and... (constant envelope) GMSK modulation is the process of sending a signal by changing the characteristics of a carrier frequency Transmission rate GSM is a digital system with an over-the-air bit rate of 270 kbps (for 8 user channels) Access method GSM utilizes the time division multiple access (TDMA) concept GSM Advantages Worldwide used with over billions of subscribers International roaming can be achieved... between these bursts for a single mobile phone user is very short GSM is based on TDMA Personal Digital Cellular (PDC) Power Time 3 2 6 5 Frequenc y 9 8 Frequency 30 KHz D-AMPS USDC: U.S Digital Cellular (D-AMPS) Another name for USDC is D-AMPS or IS-54 Digital AMPS is a variation of AMPS Uses 3-timeslot variation of TDMA, also known as Interim Standard-54 (IS-54) Is an upgrade of the analogue AMPS D-AMPS... The RAKE receiver was designed to equalize the effects of multipath It uses a combination of correlators, code generators, and delays to separate individual path signals of the multipath Each signal is then delayed and summed according to peaks found in the received signal by utilizing Searcher ∑ CDMA Advantages Higher capacity than TDMA (more # of users per cell/BW) High quality service High Security... e-mail, internet etc using their mobile phone GPRS is based on existing GSM cellular network infrastructure and adds new packet-switching network equipments A physical channel is only assigned when data needs to be transmitted or received Physical channel can be shared between different mobile users Use of packet switching means no dedicated physical channel, only allocation of physical channel dynamically... Planning NO YES YES YES Handoff Soft / Hard Hard Hard Hard Power Control Fast Slow Slow Slow Mobile Power Consumption Low Medium Medium High Standard IS-95A,SP3384 IS-54/136 IS-54 Based EIA-53.3 Speech Coder Rate 8,13Kbps 8Kbps 4Kbps - Diversity Time, Space, Freq Time, Space Time, Space Space Development from 2G to 3G Japan 1st Gen TACS 2nd Gen GSM W-CDMA/EDGE Converged TDMA/GSM family of technologies will... America, Most country 3G migration CDMA-2000 W-CDMA CDMA vs GSM History of CDMA History In 1993, TIA recognized CDMA as an IS-95 Standard Korea government promoted to commercialize the technology in two parts ETRI and Qualcomm took charge of switch design, prototype development and base station design Handset manufactures developed new mobile handsets and switching systems Core MODEM chip for CDMA communication . Evolution of Wireless Mobile Communications (I )Evolution of Wireless Mobile Communications (I) 2011. 4. 25 2011. 4. 25 HyungHyung Jin Jin ChoiChoi SungkyunkwanSungkyunkwan UniversityUniversity Evolution. BSC – Base Station Controller  MSC – Mobile Switching Center GSMGSM  GSM Frame Structure 0 1 2 3 4 5 2 044 2 045 2 046 2 047 0 1 2 3 4 47 48 49 50 0 1 2 24 25 2 048 Superframes; periodicity = 3 h 28. bands (8 24 - 849 and 869 - 8 94 MHz) as AMPS. By using TDMA instead of FDMA, IS - 54 (8 24 - 849 and 869 - 8 94 MHz) as AMPS. By using TDMA instead of FDMA, IS - 54 increases the number of users