31-07-2012, 02:42 PM
A Brief Overview of the Technologies used in Wireless Communication Networks
A Brief Overview of the Technologies.pdf (Size: 289.59 KB / Downloads: 29)
INTRODUCTION
The first generation of wireless technology used analog radio signals and it continued till 2G networks which used digital signals. 2G networks were introduced in the end of 1980s. GSM (Global System for Mobile Communications) is primary 2G communications network.
4G system provides mobile ultra-broadband Internet access. Two 4G standards are commercially deployed: The WiMax standard and the first-release Long Term Evolution (LTE) standard. International Telecommunications Union-Radio Communications Sector (ITU-R) set the peak speed requirements for 4G services at 1 Gbit/s for low mobility communication. The first release versions of WiMAX and LTE, however, do not comply totally with these requirements, but are often labeled 4G.
TECHNOLOGY IN 2G AND 4G NETWORKS
GSM
Global System for Mobile (GSM) is a second generation digital mobile standard developed to cater data delivery using digital modulation. GSM uses a variation of Time Division Multiple Access (TDMA) technology. In multiple access method, same multi-point transmission medium can be used to transmit over it through several terminals. The TDMA multiple access scheme is based on Time Division Multiplex. The same frequency channel can be shared by several users by dividing the signal into different time slots. The users transmit in rapid succession, one after the other, each using its own time slot.
CONCLUSION
The wireless industry has witnessed a phenomenal growth in the last few years and this is due to the continuous efforts of the researchers and industries in improving technology.
This paper provides a comprehensive overview of the technology in mobile wireless communication networks in 2G and 4G. The GSM mobile standard has been discussed briefly with respect to the technology used in it. The CDMA technique used in 2G networks is also studied.
The 4G standard WiMAX is explained on the basis of MIMO-SOFDMA technology used in it. The hardware used in OFDM is explained in detail with the help of a simulink matlab model.
The study is mainly theoretical based on the literature survey and important concepts are explained with the help of simulation.