Abstract: Simultaneously multiple carriers are using a transmission technique known as orthogonal frequency-division multiplexing (OFDM) for modulation. The OFDM based systems has spectral efficiency high and for inter symbol interference it is robust against, frequency selective fading channels. The signal get distortion due to the transmission of signal have high peak to average ratio is the main disadvantage of the system. At the receiver, to overcome drawback by removing weight with no distortion PAPR reducing scheme which is depends on OFDM signal which has weight is proposed. By forcing a weight on each OFDM signal which is discrete through a signal of certain kind which is band limited. Before a high power amplifier ( HPA) consider an OFDM signal which is formed with data of discrete weights, at the end of receiver the original signal can be collected completely, Meanwhile the time duration required to transmit the OFDM signal have weights is same as the original OFDM signal's time duration .Now we propose the effectiveness of the scheme through the evaluation of computer simulation results. By proposing new approach for the bit error rate (BER) analysis as well as propose a novel technique to mitigate PAPR and thereby increasing the performance of the multiple-input and multiple-output OFDM (MIMO-OFDM) system. It is observed that BER performance of the MIMO OFDM signal have weight is improved compared to clipping and filtering method this can be specified from the numerical results. This method has less PAPR value than the clipping and filtering method. Here the proposed method is simpler than that of the C and F method.

Keywords: Bit error rate, Convolution, Orthogonal Frequency Division Multiplexing (OFDM), peak-to-average-power-ratio (PAPR), weighted data.