Performance Analysis of OFDM System [Case study of optimize IFFT size for M-PSK technique]

In wireless communication, concept of parallel transmission of symbol is applied to achieve high throughput and better transmission quality. Orthogonal Frequency Division Multiplexing (OFDM) is one of the method of parallel transmission. The idea of OFDM is to split the total transmission bandwidth in to a number of orthogonal subcarriers in order to transmit the symbols using these subcarriers in parallel. In this paper M-ary PSK OFDM system has been simulated in MATLAB 7.6 to evaluate the performance of OFDM system. For this various modulation scheme such as BPSK,QPSK,16PSK and 256 PSK used in OFDM system with appropriate IFFT size, based upon the requirement of power and Bit Error Rate(BER) analysis. For selected modulation technique with a required power and BER, lookup table type arrangement has been provided to know the optimum size of IFFT. Keywords—OFDM, BER ,M-ary PSK ,SNR(Eb/No).