THE EFFECTS OF CONVOLUTIONAL CODING ON BER PERFORMANCE OF COMPANDED OFDM SIGNALS

Companding has been shown [1-3] to provide an improved reduction in the peak-to-average power ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM) transmissions, whilst also showing significant improvement in bit-error-rate (BER) performance in terms of signal-to-noise ratio (SNR) within an additive white Gaussian noise (AWGN) channel. In this paper, the influence of forward-error correction (FEC) on OFDM channel bandwidth is simulated and studied. The BER performance for hard-decision and soft-decision Viterbi decoding is also evaluated and compared for OFDM systems with and without companding. It is shown that companding together with FEC coding results in a further improvement in the BER performance and provides further reduction in PAPR, albeit the reduction is not significant.

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