Mobile Telephone System

Mobile telephone system is used for wide area voice and data communication. Cell phones have gone through three different generations, called 1G, 2G and 3G. The generations are as following:

1. Analog voice
2. Digital voice
3. Digital voice and data

These are explained as following below.

1. First generation (1G) Mobile Phones : Analog Voice 1G system used a single large transmitter and had a single channel, used for both receiving and sending. If a user wants to talk then he has to push the button that enabled the transmitter and disabled the receiver. Such systems were called push-to-talk systems, and they were installed in the late 1950’s. In 1960’s IMTS (Improved Mobile Telephone System) was installed. It also used a high-powered (20-watt) transmitter on top of a hill but it had two frequencies, one for sending and one for receiving, so push to talk button was no longer needed.
2. Second generation (2G) Mobile phones : Digital voice The first generation mobile phones was analog though second generation is digital. It enables new services such as text messaging. There was no worldwide standardization during second generation. Several different systems were developed and three have been deployed. GSM (Global System for Mobile Communications). It is the dominant 2G system.
3. Third generation (3G) Mobile Phones : Digital Voice and Data The first generation was analog voice and second generation was digital voice but 3rd generation is about digital voice and data. 3G mobile telephony is all about providing enough wireless bandwidth to keep future users happy. Apple’s iPhone is the kind of 3G device but actually it is not using exactly 3G , they used enhanced 2G network i.e. 2.5G and there is not enough data capacity to keep users happy.
4. Fourth generation (4G) Mobile Phones : Broadband Internet Access with Digital Voice and Data The fourth generation mobile phone is to access internet along with digital voice and digital data. It is more faster than 3G phones. 4G phones are capable to work like a computer. 4G phones made cloud services usable. Even after decades still there are remote areas where 4G network is not available. 
5. Fifth generation (5G) Mobile Phones : Super Fast Connectivity and More Than 4G The fifth generation mobile phones are to provide super fast connectivity. It provides superior performance with low latency. You will be able to connect more devices than 4G. As 4G network is not available all places so 5G network will take time to make a perfect level of coverage.