Generations of Mobile Wireless Technology
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| Generations of Mobile Wireless Technology
3G & 4G
ID:200600027 Wireless communication is the transfer of information over a distance without the use of enhanced electrical conductors or "wires”. The distances involved may be short (a few meters as in television remote control) or long (thousands or millions of kilometers for radio communications). When the context is clear, the term is often shortened to "wireless". It encompasses various types of fixed, mobile, and portable two-way radios, cellular telephones, Personal Digital Assistants (PDAs), and wireless networking. In this paper we will throw light on the evolution and development of various generations of mobile wireless technology along with their significance and advantages of one over the other. In the past few decades, mobile wireless technologies have experience 4 or 5 generations of technology revolution and evolution, namely from 0G to 4G. Current research in mobile wireless technology concentrates on advance implementation of 4G technology and 5G technology. Currently 5G term is not officially used. In 5G researches are being made on development of World Wide Wireless Web (WWWW), Dynamic Adhoc Wireless Networks (DAWN) and Real Wireless Word.
The first generation (1G) began in the early 80's with commercial deployment of Advanced Mobile Phone Service (AMPS) cellular networks. Early AMPS networks used Frequency Division Multiplexing Access (FDMA) to carry analog voice over channels in the 800 MHz frequency band. The second generation (2G) emerged in the 90's when mobile operators deployed two competing digital voice standards. In North America, some operators adopted IS-95, which used Code Division Multiple Access (CDMA) to multiplex up to 64 calls per channel in the 800 MHz band. Across the world, many operators adopted the Global System for Mobile communication (GSM) standard, which used Time Division Multiple Access (TDMA) to multiplex up to 8 calls per channel in the 900 and 1800 MHz bands. The International Telecommunications 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 could deliver not only voice, but also circuit-switched data at speeds 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 speeds. However, to get from 2G to 3G, mobile operators had make "evolutionary" upgrades to existing networks while simultaneously planning their "revolutionary" new mobile broadband networks. This lead to the establishment of two distinct 3G families: 3GPP and 3GPP2. The 3rd Generation Partnership Project (3GPP) was formed in 1998 to foster deployment of 3G networks that descended from GSM. 3GPP technologies evolved as follows. • General Packet Radio Service (GPRS) offered speeds up to 114 Kbps. • Enhanced Data Rates for Global Evolution (EDGE) reached up to 384 Kbps. • UMTS Wideband CDMA (WCDMA) offered downlink speeds up to 1.92 Mbps. • High Speed Downlink Packet Access (HSDPA) boosted the downlink to 14Mbps. 4G 4G is the short name for fourth-generation wireless, the stage of broadband mobile communications that will super cede the third generation (3G ). Carriers that use orthogonal frequency-division multiplexing (OFDM) instead of time division multiple access (TDMA) or code division multiple access (CDMA) are increasingly marketing their services as being 4G, even when their data speeds are not as fast as the International Telecommunication Union (ITU) specifies. According to the ITU, a 4G network requires a mobile device to be able to exchange data at 100 Mbit/sec. A 3G network, on the other hand, can offer data speeds as slow as 3.84 Mbit/sec. From the consumer's point of view, 4G is more a marketing term than a technical specification, but carriers feel justified in using the 4G label because it lets the consumer know that he can expect significantly faster data speeds. Although carriers still differ about whether to build 4G data networks using Long Term Evolution (LTE) or Worldwide Interoperability for Microwave Access WiMAX, all carriers seem to agree that OFDM is one of the chief indicators that a service can be legitimately marketed as being 4G. OFDM is a type of digital modulation in which a signal is split into several narrowband channels at different frequencies. This is more efficient than TDMA, which divides channels into time slots and has multiple users take turns transmitting bursts or CDMA, which simultaneously transmits multiple signals on the same channel. When fully implemented, 4G is expected to enable pervasive computing, in which simultaneous connections to multiple high-speed networks will provide seamless handoffs throughout a geographical area. Coverage enhancement technologies such as femtocell and picocell are being developed to address the needs of mobile users in homes, public buildings and offices, which will free up network resources for mobile users who are roaming or who are in more remote service areas. REFERENCES:
http://searchtelecom.techtarget.com/definition/3G http://searchmobilecomputing.techtarget.com/definition/4G Directory: Attachments -> BBF -> New%20folder New%20folder -> Generations of Mobile Wireless Technology New%20folder -> Misy 3312: Introduction to Telecommunications Project Proposal for Voice over Internet Protocol (VoIP) Instructor Name: Mr. Muhammad Rafiq Section 202 New%20folder -> Misy 3312: Introduction to Telecommunications New%20folder -> Career Path at Saudi Aramco Company New%20folder -> Network theory New%20folder -> Coen 1320 signals and systems spring-2013 New%20folder -> BlackBerry’s Privacy and Security Dr. Mohammed Rafik Telecommunication Submitted By New%20folder -> Smart phone Phelps Jon 16 October New%20folder -> Weekly log book student – Please fill this in at the end of the every week Download 24.71 Kb. Share with your friends:
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