1G - (or 1-G) refers to the first generation of wireless telephone technology (mobile communication). These are the analog telecommunications standards that were introduced in the 1980s and continued until being replaced by 2G digital telecommunications. The main difference between the two mobile telephone systems (1G and 2G), is that the radio signals used by 1G networks are analog, while 2G networks are digital.

Unlike its successor, 2G, which made use of digital signals, 1G wireless networks used analog radio signals. Through 1G, a voice call gets modulated to a higher frequency of about 150MHz and up as it is transmitted between radio towers. This is done using a technique called Frequency-Division Multiple Access (FDMA).

First Generation Mobile phones.

What is Second Generation .....??

2G is for second-generation wireless telephone technology.Second generation 2G cellular telecom networks were commercially launched on the GSM . Three primary benefits of 2G networks over their predecessors were that phone conversations were digitally encrypted; 2G systems were significantly more efficient on the spectrum allowing for far greater mobile phone penetration levels; and 2G introduced data services for mobile, starting with SMStext messages. 2G technologies enabled the various mobile phone networks to provide the services such as text messages, picture messages and MMS (multi media messages). All text messages sent over 2G are digitally encrypted, allowing for the transfer of data in such a way that only the intended receiver can receive and read it.

After 2G was launched, the previous mobile telephone systems were retrospectively dubbed 1G. While radio signals on 1G networks are analog,, radio signals on 2G networks are digital. Both systems use digital signaling to connect the radio towers (which listen to the handsets) to the rest of the telephone system.

2G-(SECOND GENERATION MOBILE'S)-

2G has been superseded by newer technologies such as2.5G,2.75G,3G, and4G; however, 2G networks are still used in many parts of the world.

What is 3G(Third Generation)...............??

3G, short form third generation, is the third generation of mobile telecommunication technology. This is based on a set of standards used for mobile devices and mobile telecommunications use services and networks that comply with the International Mobile Telecommunications-2000 (IMT-2000) . 3G finds application in wireless voice telephony,mobile , internet access,fixed wireless Internet access,video calls and mobile tv.

3G telecommunication networks support services that provide an information transfer rate of at least 200kbit/s. Later 3G releases, often denoted 3.5G and 3.75G, also provide mobile broadband access of several mbit/s to smartphones and mobile modems in laptop computers. This ensures it can be applied to wireless voice telephony mobile internet access,fixed wireless Internet access, video calls and mobile tv technologies.

3G Mobile phone-

A new generation of cellular standards has appeared approximately every tenth year since 1G systems were introduced in 1981/1982. Each generation is characterized by new frequency bands, higher data rates and non–backward-compatible transmission technology. The first 3G networks were introduced in 1998 and fourth generation ''4G'' networks in 2008.

4G Fourth Generation (The fast generation).

4G, short for fourth generation, is the fourth generation of mobile telecommunication technology, succeeding 3G and preceding 5G. A 4G system, in addition to the usual voice and other services of 3G, provides mobile broadband Internet access, for example to laptops with wireless modems, to smartphones, and to other mobile devices. Potential and current applications include amended mobile web access, IP technology, gaming services,high definition mobile tv video conferencing, 3D television, and cloud computing.

Two 4G candidate systems are commercially deployed: the mobile WMAX standard (first used in South Korea in 2007), and the first-release long term evolution (LTE) standard (in Oslo, Norway and Stockholm, Sweden since 2009). It has however been debated if these first-release versions should be considered to be 4G or not, as discussed in the technical definition section below.

Difference between 3G and 4G-

In one word: fast! To be technical, 4G stands for “4th generation” mobile data protocol. But as a growing band of 4G users will tell you, it’s all about the speed. Now, what is 4G LTE? LTE stands for Long Term Evolution. It’s a term used for the particular 4G protocol that delivers the fastest mobile Internet experience. Some experts even refer to it as “true 4G.” A 4G LTE network is therefore one that operates at the leading edge of speed and reliability. Using a 4G smartphone on Verizon’s 4G LTE network means you can download files from the Internet up to 10 times faster than with 3G. With 4G LTE, using the web from your phone becomes as pleasurable as using it from your home computer. To join the 4G revolution, you need to have a smartphone that is configured to work with a 4G network and a mobile plan . All 4G phones offered by Verizon will work with its 4G LTE network, the largest in the U.S. These phones will connect automatically with the 4G LTE network, but they can also connect to and use the 3G network (at 3G speed) in places where 4G LTE service is not yet available. So there you have it. 3G speeds laid the groundwork for our increasingly mobile lifestyle, but 4G speeds are truly taking “mobile” to the next level.

Different Generation Mobile Phone's.

Comparison of All Generation's-

Difference between 2G and 3G-

Here we can see the differnce betwen 2g and 3g in downloading speed,calling process, messaging and video on demand.

Difference between in 3G and 4G-

Data speed of 3G is 3mb/sec. under CDMA (code division multiple access).And network used is wide area cell based ,while in 4G data speed is 1gb/sec .Under WIMAX2 and LTE advance .And network used wide area network(WAN).Frequency of 3G is 1.8-2.5 ghz whereas 4G is 2-8 ghz.