Bit Error Rate Performance of OFDM/OQPSK and CPM with Channel Coding Over AWGN Channel

Abstract

In this paper, Bit Error Rate performance of Orthogonal Frequency Division Multiplexing/Offset Quadrature Phase Shift Keying (OFDM/OQPSK) and Continuous Phase Modulation (CPM) over Additive White Gaussian Noise (AWGN) channel is presented. The Bit Error Rate (BER) performance for OFDM/OQPSK and CPM is compared in two separate simulations. The first without channel coding while the second with the block and convolutional coding scheme. The use of OFDM has proven to be effective as its sub carriers are orthogonal to each other providing the advantage of lesser inter-symbol interference. The simulation setup is such that signals are generated from a Bernoulli binary source where they undergo modulation by OFDM/OQPSK and CPM in separate simulations before entering the AWGN channel after which demodulation takes place. Outputs from the demodulator goes into the error rate calculator where charts showing the bit error rates are obtained. The simulation results showed a bit error rate of 1.7402e-05 at the 5dB point for the OFDM/OQPSK case with convolutional block coding while the block coding error correction technique had a slightly higher BER of 0.0074 due to its hard-decoding. Lastly, the no coding case had the highest BER of 0.0125 at the 5db point due to the absence of any error correction technique.