This paper studies the performance of coded orthogonal frequency division multiplexing system using two modulation techniques, quadrature phase shift keying(QPSK) and quadrature amplitude modulation(QAM). The convolutional code is used as error-correcting-code. The communication channel used is vehicular channel. Simulation results show that the performance of coded orthogonal frequency division multiplexing system with QPSK is better than that with QAM
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