Bit Error Performance of Variations along the Spectrum for the Several Sub Carrier

Abstract

Present scenario of mobile communication is to meet the demands of Error free and high data rate communication. This can be achieved with multi carrier modulation technique. In Multi carrier modulation, the transmitting data is split into several components which is modulated and transmitted with different carriers which leads to less Inter Symbol Interference, multipath fading and impulse noise. A novel method of multi carrier modulation and demodulation was done by multiplying user symbols with several sub carriers then combining the several modulated signals and transmitted over a noisy channel. Analysis was carried out after demodulation by comparing received symbols with transmitted symbols. Simulation was carried out to analyze the Bit error rate (BER) performance of multi carrier modulation system as a function of Number of sub carriers and spacing between them. It is found that BER performance is not consistent for all sub carriers. BER performance degrades as sub carriers increases from 1 to n, where n=fs/2. It is also observed that the BER performance is approximately stable throughout the specified spectrum for a given sub carrier.