The telecommunication service in World had a great leap within a last few year. About 6 billion people own a mobile phones so we are going to analyze the various generations of cellular systems as studied in the evolution of mobile communications from 1st generation to 5th generation. Now almost all the service providers as well as the customers seek for availing these 3G and 4G services. We can analyze that this could be due to increase in the telecoms customers day by day. In the present time, there are four generations in the mobile industry. These are respectively 1G the first generation, 2G the second generation, 3G the third generation, and then the 4G the fourth generation.
Wireless telephone started with what might be called as 0G. The great ancestor is the mobile telephone service that became available just after World War II. In those pre-cell days, we had a mobile operator to set up the calls and there were only a handful of channels available. In 1G, Narrow Band Analogue Wireless network is used, with this we can have the voice calls and can send text messages. These services are provided with circuit switching. Then in case of 2G Narrow Band Wireless Digital Network is used. It brings more clarity to the conversation. Wireless phone standards have a life of their own. You can tell, because they're spoken of reverently in terms of generations. There's great-granddad who's pioneering story pre-dates cellular, grandma and grandpa analog cellular, mom and dad digital cellular, 3G wireless just starting to make a place for itself in the world, with the new baby “4G” on the way, and “5G” is in thought process.
The big boom in mobile phone service really began with the introduction of analog cellular service called AMPS (Analog Mobile Phone Service) starting in 1981. This generation is 1G, the first for using cell technology that let users place their own calls and continue their conversations seamlessly as they moved from cell to cell. AMPS uses what is called FDM or frequency division multiplexing. Each phone call uses separate radio frequencies or channels. The next generation, quick on the heels of the first, is digital cellular. One standard uses a digital version of AMPS called D-AMPS using TDMA (Time division Multiple Access). A competing system also emerged using CDMA or Code Division Multiple Access.
Digital transmissions allow for more phone conversations in the same amount of spectrum. They also lay the groundwork for services beyond simple voice telephone calls. Data services such as Internet access, text messaging, sharing pictures and video are inherently digital. This is where the whole "G" thing got started. The original analog and digital cellular services were invented to cut the wire on landline phone service and give regular telephone service to move with. As such, the bandwidth they offer for adding data services is pretty meager, in the low Kbps region. Now that a cell phone is not merely a cell phone, but also a PDA, a messaging system, a camera, an Internet browser, an email reader and soon to be a television set, true broadband data speeds are needed. That new generation of cell phone service has been dubbed 3G for 3rd generation.
Both the 1G and 2G deals with voice calls and has to utilize the maximum bandwidth. In 3G Wide Brand Wireless Network is used with which the clarity increases and gives the perfection as like that of a real conversation. The data are sent through the technology called Packet Switching. Voice calls are interpreted through Circuit Switching. 3G has proven to be a tough generation to launch. The demand for greater bandwidth right now has spawned intermediate generations called 2.5G and even 2.75G. One such standard is GPRS (General Packet Radio Services) which is an extension of the GSM digital cellular service popular in Europe. It offers download speeds up to 144 Kbps. 3G phones and services are just starting to come into their own. One service you'll find is called EVDO which stands for EVolution Data Only. EVDO has download speeds up to 2.4 Mbps, which is faster than T1, DSL or Cable broadband service. There is also an evolution that includes voice called EVDV which is in the works. While 3G is going to enable telephones to also become Internet computers, video phones and television receivers, its maturity phase will find it competing with wireless VoIP telephone services on WiFi, WiMAX, WiTV and the new wireless mobile standard 802.20, which doesn't seem to have a catchy name yet. The slug-fest between analog wireline phone service and wired VoIP seems likely to be continued on the wireless front.
There is also an emerging cellular standard we should be aware of called 4G. With the case of 4G in addition to that of the services of 3G some additional features such as Multi-Media Newspapers, also to watch T.V programs with the clarity as to that of an ordinary T.V. are available. In addition, we can send Data much faster than that of the previous generations. The fourth generation being championed in Japan will boost the data rates to 20 Mbps. These speeds enable high quality video transmission and rapid download of large music files. The first 4G phones may soon and that means we better starting thinking about what to do with 5G if this generation thing is going to continue.source
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