BER performance of OFDM-BPSK ,-QPSK ,-QAM over AWGN channel using forward Error correcting code

1619 | P a g e Abstract High bit error rates of the wireless communication system require employing forward error correction (FEC) methods on the data transferred to reducing the error in transmission. In this paper, the performance of OFDMBPSK,QPSK and -QAM system by using forward error correcting codes(convolutional , reed Solomon as well as concatenated coding) schemes that are used to encode the data stream in wireless communications AWGN channel has been reported here . We present OFDM for wireless communications .We address basic OFDM and related modulations, as well as techniques to improve the performance of OFDM for wireless communications (OFDM). we performed various simulations to find out the best BER performance of each of the Convolutional and Reed-Solomon codes and used these best outcomes to model the RS-CC concatenated codes. By concatenating two different codes we can get the effect of improving the total BER due to benefits of RS codes correcting burst errors while convolutional codes are good for correcting random errors that are caused due to a noisy channel.

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