Performance of Turbo Coded OFDM in Wireless Application

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) has become a popular
modulation method in high speed wireless communications. By partitioning a wideband
fading channel into flat narrowband channels, OFDM is able to mitigate the detrimental
effects of multi path fading using a simple one- tap equalizer. There is a growing need to
quickly transmit information wirelessly and accurately.
Engineers have already combine techniques such as OFDM suitable for high data rate
transmission with forward error correction (FEC) methods over wireless channels. In this
thesis, we enhance the system throughput of a working OFDM system by adding turbo
coding. The smart use of coding and power allocation in OFDM will be useful to the desired
performance at higher data rates.
Error control codes have become a vital part of modern digital wireless systems,
enabling reliable transmission to be achieved over noisy channels. Over the past decade,
turbo codes have been widely considered to be the most powerful error control code of
practical importance. In the same time-scale, mixed voice/data networks have advanced
further and the concept of global wireless networks and terrestrial links has emerged. Such
networks present the challenge of optimizing error control codes for different channel types,
and for the different qualities of service demanded by voice and data.