Orthogonal Frequency Division Multiplexing (OFDM) is one of the latest modulation

techniques used in order to combat the frequency-selectivity of the transmission channels,

achieving high data rate without inter–symbol interference. The basic principle of OFDM is

gaining a wide spread popularity within the wireless transmission community. Furthermore,

OFDM is one of the main techniques proposed to be employed in 4 th Generation Wireless

Systems. Therefore, it is crucial to understand the concepts behind OFDM. In this paper it is

given an overview of the basic principles on which this modulation scheme is based.