Employment of pulse shaping techniques for efficient PAPR reduction in OFDM system

摘要

This paper aims at contributing to find out the best pulse shaping technique to reduce peak to average power ratio (PAPR) for OFDM system efficiently. At first different narrowband pulses (Sine, Tukey window and Kaiser window) as well as broadband pulses (Raised cosine and Square root raised cosine pulse) have been employed in the transmitter section. In order to carry out the performance analysis, a mathematical model is derived for each of the above employed pulse shaping techniques which includes equations for PAPR and cross correlation. The proposed technique needs only one IFFT/FFT in the transceiver and does not require any side information. Based on this model, a performance comparison is carried out between all the mentioned narrowband and broadband pulses. Numerical result shows that the square root raised cosine pulse reduces the PAPR more significantly than any other pulse and the existing system as well. Furthermore cross correlation function is also examined for both narrowband and broadband pulses. Finally in order to show the efficacy of the proposed efficient pulse shaping technique (Square root raised cosine pulse), bit error rate (BER) is calculated and compared with the conventional system. Simulation result shows that the proposed scheme can reduce the BER more effectively than the conventional system. Therefore, square root raised cosine pulse can be used not only to reduce the PAPR of OFDM system effectively but also to improve the BER performance of the system.