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  • Mobile phones was invented by Dr.Martin cooper in April 3,1973.
  • Mobile phone has become the best mode of communication.
  • It was first used in United States of America
  • Now we have 1G,2G,3G models.
  • The upcoming model is 4G.

CONTENTS:

In telecommunications, 4G is the fourth generation of cell phone mobile communications  standards. It is a successor of the third generation standards. A 4G system provides mobile ultra-broadband Internet access, for example to laptops with USB wireless modems, to smartphones, and to other mobile devices. Conceivable applications include amended mobile web access,IP telephony, gaming services, high-definition mobile TV, video conferencing and 3D television.

Two 4G candidate systems are commercially deployed: The Mobile WiMAX standard (at first in South Korea in 2006), and the first-release Long term evolution (LTE) standard (in Scandinavia since 2009). It has however been debated if these first-release versions should be considered as 4G or not. See technical definition.

IMT-Advanced Requirements

This article uses 4G to refer to IMT-Advanced (International Mobile Telecommunications Advanced), as defined by ITU-R. An IMT-Advanced cellular system must fulfill the following requirements:

  • Based on an all-IP packet switched network.
  • Peak data rates of up to approximately 100 Mbit/s for high mobility such as mobile access and up to approximately 1 Gbit/s for low mobility such as nomadic/local wireless access.
  • Dynamically share and use the network resources to support more simultaneous users per cell.
  • Scalable channel bandwidth 5-20 MHz, optionally up to 40 MHz.
  • Peak link spectral efficiency of 15 bit/s/Hz in the downlink, and 6.75 bit/s/Hz in the uplink (meaning that 1 Gbit/s in the downlink should be possible over less than 67 MHz bandwidth).
  • System spectral efficiency of up to 3 bit/s/Hz/cell in the downlink and 2.25 bit/s/Hz/cell for indoor usage.
  • Smooth handovers across heterogeneous networks.
  • Ability to offer high quality of service for next generation multimedia support.

In September 2009, the technology proposals were submitted to the International Telecommunication Union (ITU) as 4G candidates. Basically all proposals are based on two technologies:

  • LTE Advanced standardized by the 3GPP
  • 802.16m standardized by the IEEE (i.e. WiMAX)

Implementations of Mobile WiMAX and first-release LTE are largely considered a stopgap solution that will offer a considerable boost until WiMAX 2 (based on the 802.16m spec) and LTE Advanced are deployed. The latter standard versions were ratified in spring 2011, but are still far from being implemented.