Analysis and System Level Simulation of BER on different Modulation Techniques using OFDM

OFDM is a modulation technique in which multiple carriers are overlapped orthogonally so that to transmit information. In this paper different modulation techniques are used with respect to the number of bits transmitted and the bit error rate (BER). The result shows that by modulating a signal at a fixed subcarrier for different modulation technique, the error in the data increases rapidly, whereas in case of fixed modulation techniques, increasing number of subcarrier the error in the data is constant and varies by a small fraction. Thus it is efficient to use the OFDM technique at a fixed modulation bits with increasing subcarriers. The simulation shows that by increasing the number of bits in a particular modulation technique, there is an increase in data rate thus compromising on error rate. Key-Words: OFDM, BER, Sub carrier, Fast Fourier Transform (FFT) and Inverse Fast Fourier Transform (IFFT).