4g Communications Essay

4G COMMUNICATIONS Sai srinivas BTECH III/IV,ECE Sai. srinivas. [email protected] com Adepu sravanthi Adepu.

[email protected] com Abstract Fourth generation (4G) communication systems require bandwidth efficiency and low complexity receivers to accommodate high data rates and large number of users per cell. This paper provides an introduction to a novel approach for uplink scenario in 4G mobile communication called multi-carrier interleave-division multiple-access (MC-IDMA).In this paper basic principles of interleave division multiple access (IDMA), orthogonal frequency division multiple access (OFDMA), and MC-IDMA are outlined.

Comparisons are carried out between IDMA, MC-IDMA and multi-carrier code division multiple-access (MC-CDMA). The advantages of MC-IDMA over its competitive techniques are demonstrated. It is shown that MC-IDMA can be leading candidate for 4G mobile systems with its attractive advantages such as flexible rate adaptation, frequency diversity and multi user gain.Objectives 4G is being developed to accommodate the QoS and rate requirements set by further development of existing 3G applications like wireless broadband access, Multimedia Messaging Service (MMS), video chat, mobile TV, but also new services like HDTV content, minimal services like voice and data, and other services that utilize bandwidth. It may be allowed roaming with wireless local area networks, and be combined with digital video broadcasting systems.The 4G working group[clarification needed] has defined the following as objectives of the 4G wireless communication standard: Flexible channel bandwidth, between 5 and 20 MHz, optionally up to 40 MHz. [2] A nominal data rate of 100 Mbit/s while the client physically moves at high speeds relative to the station, and 1 Gbit/s while client and station are in relatively fixed positions as defined by the ITU-R,[6] A data rate of at least 100 Mbit/s between any two points in the world CURRENTLY USED TECHNOLOGY: TDMA CDMA {draw:frame} draw:frame} CDMA: Code division multiple access (CDMA) is a channel access method utilized by various radio communication technologies.

It should not be confused with the mobile phone standards called cdmaOne and CDMA2000 (which are often referred to as simply “CDMA”), which use CDMA as an underlying channel access method. {draw:frame} {draw:frame} {draw:frame} Receiving Data Using CDMA 4G features&technologies: According to the members of the 4G working group, the infrastructure and the terminals of 4G will have almost all the standards from 2G to 4G implemented.Although legacy systems are in place to adopt existing users, the infrastructure for 4G will be only packet-based (all-IP). Some proposals suggest having an open Internet platform. Technologies considered to be early 4G include: Flash-OFDM, the 802. 16e mobile version of WiMax (also known as WiBro in South Korea) OFDMA {draw:frame} Orthogonal Frequency-Division Multiple Access (OFDMA) is a multi-user version of the popular Orthogonal frequency-division multiplexing (OFDM) digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users as shown in the illustration below.

This allows simultaneous low data rate transmission from several users. MIMO: Multiple input multiple output multiple-input and multiple-output, or MIMO (commonly pronounced my-moh or me-moh), is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology. {draw:frame} 4G HARDWARE: UWB Networks Smart Antennas SMART ANTENNAS HELP TO..

.. Optimize available power Increase base station range and coverage Reuse available spectrum Increase bandwidth Lengthen battery life of wireless devicesSwitched Beam Antennas {draw:frame} Adaptive Array Antenna {draw:frame} Locating And Tracking The User UWB: Ultra Wide Band Networks {draw:frame} 4G SOFTWARE: Software Defined Radio Packet Layer Packets PACKETS ARE…. : More Secure More Flexible More reliable Easier To Standardize Extensible APPLICATIONS: 4G And Public Safety Sensors On Public Vehicles Cameras In Traffic Lights Traffic During Disasters Tracking And Tracing Conclusion: today’s wired society is going wireless, and it has a problem. 4G is the answer 4G must be standardised as the next wireless systems