Implementing Orthogonal Frequency Division Multiplexing Using IFFT/FFT

Orthogonal Frequency Division Multiplexing (OFDM) is a modulation system that offers many advantages over other modulation scheme. OFDM is a particular form of Multi-carrier transmission and is suited for frequency selective channels and high data rates; it overcomes the Inter Symbol Interference(ISI) problem by modulating multiple narrow-band sub-carriers in parallel. In this paper, analysis of OFDM is carried out with emphasis on the implementation using IFFT/FFT as against multiple Oscillators and demodulators. The concept of orthogonality of carriers is used to explain the ability to transmit multi-carriers without interference and the ease of decoupling the signal information at the receivers. Matlab simulations were carried out to show these concept