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  2. 2. INTRODUCTION <ul><li>International Mobile Telecommunications-2000 (IMT-2000), better known as 3G or 3rd Generation , is a family of standards for mobile telecommunications defined by the International Telecommunication Union, which includes GSM, EDGE, UMTS, and CDMA2000 as well as DECT and WiMAX. Services include wide-area wireless voice telephone, video calls, and wireless data, all in a mobile environment. Compared to 2G and 2.5G services, 3G allows simultaneous use of speech and data services and higher data rates (up to 14.0 Mbit/s on the downlink and 5.8 Mbit/s on the uplink with HSPA+). Thus, 3G networks enable network operators to offer users a wider range of more advanced services while achieving greater network capacity through improved spectral efficiency. The International Telecommunication Union (ITU) defined the third generation (3G) of mobile telephony standards – IMT-2000 – to facilitate growth, increase bandwidth, and support more diverse applications. For example, GSM (the current most popular cellular phone standard) could deliver not only voice, but also circuit-switched data at download rates up to 14.4 kbps. But to support mobile multimedia applications, 3G had to deliver packet-switched data with better spectral efficiency, at far greater bandwidths. </li></ul>
  3. 3. 3G STANDARDS <ul><li>GSM </li></ul><ul><li>EDGE </li></ul><ul><li>CDMA2000 </li></ul><ul><li>UMTS </li></ul><ul><li>DECT </li></ul><ul><li>WiMAX </li></ul>
  4. 4. GSM GSM is the most popular standard for mobile phones in the world Its ubiquity makes international roaming very common between mobile phone operators , enabling subscribers to use their phones in many parts of the world. GSM differs from its predecessors in that both signaling and speech channels are digital , and thus is considered a second generation ( 2G ) mobile phone system. <ul><li>Technical details </li></ul><ul><ul><li>Cellular radio network </li></ul></ul><ul><ul><li>Frequencies </li></ul></ul><ul><ul><li>Network structure </li></ul></ul><ul><ul><li>Subscriber Identity Module (SIM) </li></ul></ul><ul><ul><li>Phone locking </li></ul></ul><ul><ul><li>GSM security </li></ul></ul>( Global System for Mobile communications)
  5. 5. Cellular radio network <ul><li>GSM is a cellular network. </li></ul><ul><li>There are five different cell sizes in a GSM network . </li></ul><ul><ul><ul><ul><ul><li>macro </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>micro </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>pico </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>femto </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>umbrella </li></ul></ul></ul></ul></ul>
  6. 6. Frequencies <ul><ul><li>GSM networks operate in a number of different frequency ranges (separated into GSM frequency ranges for 2G and UMTS frequency bands for 3G). Most 2G GSM networks operate in the 900 MHz or 1800 MHz bands. Some countries in the Americas (including Canada and the United States) use the 850 MHz and 1900 MHz bands because the 900 and 1800 MHz frequency bands were already allocated. Most 3G GSM networks in Europe operate in the 2100 MHz frequency band. The rarer 400 and 450 MHz frequency bands are assigned in some countries where these frequencies were previously used for first-generation systems.GSM-900 uses 890–915 MHz to send information from the mobile station to the base station (uplink) and 935–960 MHz for the other direction (downlink), providing 125 RF channels (channel numbers 1 to 124) spaced at 200 kHz. Duplex spacing of 45 MHz is used. </li></ul></ul>
  7. 7. Network structure <ul><li>The Base Station Subsystem. </li></ul><ul><li>The Network and Switching Subsystem. </li></ul><ul><li>The GPRS Core Network (the optional part which allows packet based Internet connections). </li></ul>
  8. 8. Subscriber Identity Module (SIM) <ul><li>One of the key features of GSM is the Subscriber Identity Module, commonly known as a SIM card . The SIM is a detachable smart card containing the user's subscription information and phone book. This allows the user to retain his or her information after switching handsets. Alternatively, the user can also change operators while retaining the handset simply by changing the SIM. Some operators will block this by allowing the phone to use only a single SIM, or only a SIM issued by them; this practice is known as SIM locking, and is illegal in some countries. </li></ul>
  9. 9. GSM security <ul><li>GSM was designed with a moderate level of security. The system was designed to authenticate the subscriber using a pre-shared key and challenge-response. Communications between the subscriber and the base station can be encrypted. </li></ul>
  10. 10. EDGE ( Enhanced Data rates for GSM Evolution ) <ul><li>extension of standard GSM </li></ul><ul><li>provides more than three-fold increase in both the capacity and performance of GSM/GPRS networks. </li></ul><ul><li>can be used for any packet switched application, such as an Internet connection </li></ul><ul><li>Peak bit-rates of up to 1Mbit/s and typical bit-rates of 400kbit/s can be expected. </li></ul>
  11. 11. CDMA2000 <ul><li>also known as IMT Multi‑Carrier (IMT‑MC) </li></ul><ul><li>based on CDMA, to send voice, data, and signaling data between mobile phones and cell sites. </li></ul><ul><li>The set of standards includes: CDMA2000 1X, CDMA2000 EV-DO Rev. 0r, CDMA2000 EV-DO Rev. A, and CDMA2000 EV-DO Rev. B. </li></ul><ul><li>1X </li></ul><ul><li>The designation &quot;1x&quot;, meaning 1 times Radio Transmission Technology </li></ul><ul><li>supports packet data speeds of up to 153 kbps </li></ul><ul><li>1xEV-DO </li></ul><ul><li>wireless transmission of data through radio signals, typically for broadband Internet access . </li></ul><ul><li>Including CDMA and TDMA </li></ul>Access schemes For radio systems there are two resources, frequency and time. Division by frequency, so that each pair of communicators is allocated part of the spectrum for all of the time, results in Frequency Division Multiple Access (FDMA). Division by time, so that each pair of communicators is allocated all (or at least a large part) of the spectrum for part of the time results in Time Division Multiple Access (TDMA). In Code Division Multiple Access (CDMA), every communicator will be allocated the entire spectrum all of the time. CDMA uses codes to identify connections.
  12. 12. UMTS (Universal Mobile Telecommunications System ) <ul><li>The most common form of UMTS uses </li></ul><ul><li> </li></ul>W-CDMA (UTRA-FDD) W-CDMA uses the DS-CDMA channel access method with a pair of 5 MHz channels. In contrast, the competing CDMA2000 system uses one or more arbitrary 1.25 MHz channels for each direction of communication. W-CDMA systems are widely criticized for their large spectrum usage, which has delayed deployment in countries that acted relatively slowly in allocating new frequencies specifically for 3G services (such as the United States). <ul><li>W-CDMA </li></ul><ul><li>TD-CDMA </li></ul><ul><li>TD-SCDMA </li></ul>UTRA-TDD HCR UMTS-TDD's air interfaces that use the TD-CDMA channel access technique are standardized as UTRA-TDD HCR, which uses increments of 5 MHz of spectrum, each slice divided into 10ms frames containing fifteen time slots (1500 per second). The time slots (TS) are allocated in fixed percentage for downlink and uplink. TD-CDMA is used to multiplex streams from or to multiple transceivers. Unlike W-CDMA, it does not need separate frequency bands for up- and downstream, allowing deployment in tight frequency bands. TD-CDMA is a part of IMT-2000 as IMT CDMA TDD. TD-SCDMA (UTRA-TDD 1.28 Mcps Low Chip Rate) TD-SCDMA uses the TDMA channel access method combined with an adaptive synchronous CDMA component on 1.6 MHz slices of spectrum, allowing deployment in even tighter frequency bands than TD-CDMA. However, the main incentive for development of this Chinese-developed standard was avoiding or reducing the license fees that have to be paid to non-Chinese patent owners. Unlike the other air interfaces, TD-SCDMA was not part of UMTS from the beginning but has been added in Release 4 of the specification. Like TD-CDMA, it is known as IMT CDMA TDD within IMT-2000. Interoperability and global roaming UMTS phones (and data cards) are highly portable—they have been designed to roam easily onto other UMTS networks (assuming the providers have roaming agreements in place). In addition, almost all UMTS phones are UMTS/GSM dual-mode devices, so if a UMTS phone travels outside of UMTS coverage during a call the call may be transparently handed off to available GSM coverage. Roaming charges are usually significantly higher than regular usage charges.
  13. 13. DECT ( Digital Enhanced Cordless Telecommunications ) <ul><li>known as Digital European Cordless Telephone </li></ul><ul><li>standard for digital portable phones (cordless home telephones), commonly used for domestic or corporate purposes. </li></ul><ul><li>to access a fixed telecoms network via radio. </li></ul>
  14. 14. WiMAX (Worldwide Interoperability for Microwave Access ) <ul><li>The technology provides up to 10 Mbit/s broadband speeds without the need for cables. </li></ul><ul><li>Uses </li></ul><ul><ul><li>Connecting Wi-Fi hotspots to the Internet. </li></ul></ul><ul><ul><li>Providing a wireless alternative to cable and DSL for &quot;last mile&quot; broadband access. </li></ul></ul><ul><ul><li>Providing data and telecommunications services. </li></ul></ul><ul><ul><li>Providing a source of Internet connectivity as part of a business continuity plan. That is, if a business has both a fixed and a wireless Internet connection, especially from unrelated providers, they are unlikely to be affected by the same service outage. </li></ul></ul>
  15. 15. OVERVIEW OF 3G <ul><li>Can also be used as an upgrade to PDC or D-AMPS. </li></ul><ul><li>Also known as FOMA UMTS is the common name for a standard that encompasses multiple air interfaces. </li></ul><ul><li>Also known as UTRA-FDD; W-CDMA is sometimes used as a synonym for UMTS, ignoring the other air interface options. </li></ul><ul><li>Also known as UTRA-TDD 3.84 Mcps high chip rate (HCR) </li></ul><ul><li>Also known as UTRA-TDD 1.28 Mcps low chip rate (LCR) </li></ul>
  16. 16. HISTORY <ul><li>The first pre-commercial 3G network was launched by NTT DoCoMo in Japan branded FOMA, in May 2001 on a pre-release of W-CDMA technology.The first commercial launch of 3G was also by NTT DoCoMo in Japan on 1 October 2001, although it was initially somewhat limited in scope;broader availability was delayed by apparent concerns over reliability. The second network to go commercially live was by SK Telecom in South Korea on the 1xEV-DO technology in January 2002. By May 2002 the second South Korean 3G network was by KT on EV-DO and thus the Koreans were the first to see competition among 3G operators. </li></ul>
  17. 17. FEATURES <ul><li>Data rates </li></ul><ul><li>ITU has not provided a clear definition of the data rate users can expect from 3G equipment or providers. Thus users sold 3G service may not be able to point to a standard and say that the rates it specifies are not being met. While stating in commentary that &quot;it is expected that IMT-2000 will provide higher transmission rates: a minimum data rate of 2 Mbit/s for stationary or walking users, and 348 kbit/s in a moving vehicle,&quot; the ITU does not actually clearly specify minimum or average rates or what modes of the interfaces qualify as 3G, so various rates are sold as 3G intended to meet customers expectations of broadband data. </li></ul>Security 3G networks offer a greater degree of security than 2G predecessors. By allowing the UE (User Equipment) to authenticate the network it is attaching to, the user can be sure the network is the intended one and not an impersonator.
  18. 18. APPLICATIONS <ul><li>The bandwidth and location information available to 3G devices gives rise to applications not previously available to mobile phone users. Some of the applications are: </li></ul><ul><li>Mobile TV - a provider redirects a TV channel directly to the subscriber's phone where it can be watched. </li></ul><ul><li>Video on demand - a provider sends a movie to the subscriber's phone. </li></ul><ul><li>Video conferencing - subscribers can see as well as talk to each other. </li></ul><ul><li>Tele-medicine - a medical provider monitors or provides advice to the potentially isolated subscriber. </li></ul><ul><li>Location-based services - a provider sends localized weather or traffic conditions to the phone, or the phone allows the subscriber to find nearby businesses or friends </li></ul>
  20. 20. THANK YOU…