Bit Error Rate Performance of QPSK Modulation and OFDM-QPSK with AWGN and Rayleigh Multipath Channel

In this paper Bit Error Rate performance of QPSK modulation and OFDM -QPSK System over AWGN and Rayleigh fading channel is analyzed. The performance of BER of QPSK over AWGN and Rayleigh channel is compared. OFDM is an orthogonal frequency division multiplexing to reduce intersymbol interference problem. Simulation of QPSK signals is carried with both AWGN and Rayleigh channel. Finally simulations of OFDM signals are carried with Rayleigh faded signals to understand the effect of channel fading and to obtain optimum value of Bit Error Rate (BER) and Signal to noise ratio (SNR). The simulation results show that the simulated bit error rate is in good agreement with the theoretical bit error rate for QPSK modulation