C.D.DIVYA KUM ARI P.ARCHANA II B-TECH II B-TECH CSIT CSIT GPREC GPREC
Communication is exchange of ideas. Communication plays a very imp role in life. In early days people use to send messages through pigeons and letters. Later through telegrams. But this way communication is very slow. Telephones are replaced by telegrams, letters. Mobile completely revolutionalized communication bcoz it is the fastest way of communication. Mobile Communication: A communication network (either public or private) which doesn't depend on any physical connection between two communication entities and have flexibility to be mobile during communication. The current GSM and CDMA technologies offer Mobile Communication.
Generations of mobile communication are as follows: 1G:
In the world of cell phones, 1G signifies first-generation wireless analog technology standards that originated in the 1980s. The 1G or First Generation was developed in the seventies. This technology was used for voice transfer. But 1G technology has Poor voice quality, Poor battery life, large phone size, No security, frequent call drops, Limited capacity and poor handoff reliability. 2G:
2G first appeared around the end of the 1980’s, the 2G system digitized the voice signal. It is later developed as 2.5G. This technology includes TDMA, GSM, and CDMA. The GSM is a circuit switched, connection oriented technology, where the end systems are dedicated for the entire call session. This causes inefficiency in usage of bandwidth and resources. The GSM-enabled systems do not support high data rates. They are unable to handle complex data such as video. 3G:
3G is the third generation of mobile phone standards and technology. 3G supersedes 2G technology and precedes 4G technology. 2.5G was a temporary bridge between 2G and 3G. 3G technologies enabled faster data-transmission speeds, greater network capacity and more advanced network services. This technology delivers data speed from 384kbps to 2 Mbps. But 3G has High bandwidth requirement, High spectrum licensing fees, and huge capital. 4G:
4G, which is also known as “beyond 3G” or “fourth-generation” cell phone technology, refers to the entirely new evolution and a complete 3G replacement in wireless communications. Fourth generation mobile communications will have higher data transmission rates than 3G. What is 4G?
4G takes on a number of equally true definitions, depending on who you are talking to. In simplest terms, 4G is the next generation of wireless networks that will replace 3G networks sometimes in future. In another context, 4G is simply an initiative by academic R&D labs to move beyond the limitations and problems of 3G which is having trouble getting deployed and meeting its promised performance and throughput. . 4G mobile data transmission rates are planned to be up to 100 megabits per second on the move and 1000gigbits per second stationary, this is a phenomenal amount of bandwidth, only comparable to the bandwidth workstations get connected directly to a LAN. Motivation for 4G Research Before 3G Has Not Been Deployed?
•3G performance may not be sufficient to meet needs of future high-performance applications like multi-media, full-motion video, wireless teleconferencing. We need a network technology that extends 3G capacity by an order of magnitude. •There are multiple standards for 3G making it difficult to roam and interoperate across networks. we need global mobility and service portability •3G is based on primarily a...