The demand of high data rate services has been increasing very rapidly and there

is no slowdown in sight. We know that the data transmission includes both wired

and wireless medium. Often, these services require very reliable data transmission

over very harsh environment. Most of these transmission systems experience much

degradation such as large attenuation, noise, multipath, interference, time variance,

nonlinearities and must meet the finite constraints like power limitation and cost

factor. One physical layer technique that has gained a lot of popularities due to

its robustness in dealing with these impairments is multi-carrier modulation technique.

In multi-carrier modulation, the most commonly used technique is Orthogonal

Frequency Division Multiplexing (OFDM)