The Orthogonal Frequency Division Multiplexing (OFDM) technique has become extremely well-liked technique in the last two decades. It is a bandwidth efficient signalling scheme for bandwidth digital communications. The present and upcoming generation of communication system depends mainly on such technique, because of its skill to combat multipath fading channels using the analogous concept of cyclic prefix (Guard Interval).With OFDM, it is possible to use a differential coding/differential detection either in the time or frequency domain bank on the condition of transmission channels with the adoption of DQPSK as a method of subcarrier modulation. It is crucial to understand the concepts behindOFDM. In whole architecture, the entire mathematicalmanoeuvring occur in transmitter and receiver block i.e. IFFT and FFT block correspondingly. The speed augmentation is the key contribution of the main processing blocks in OFDM system. In this paper, the authors will discuss the basics of OFDM system using 4 sub carriers over the AWGN channel providing DQPSK modulation. Simulation has been performed on the MATLAB so that, the graphical output will be optimized for interaction and some of its prospective and consequences have been studied.
