Abstract:Aiming at the high peak to average power ratio of the filter bank multi-carrier system with offset quadrature amplitude modulation, the DFT-spreading technology is improved and applied to FBMC/OQAM system, a technology called Pruned-DFTs which by removing the input base pulse to spread DFT matrix has been proposed. By removing the base pulse in the DFT matrix, symbols on fewer subcarriers at the transmitter are mapped to more subcarriers for transmission, which reduces the overlap between subcarriers to decrease the PAPR of the FBMC/OQAM system and makes the system have better performance in terms of peak to average power ratio.This technique fully exploits the single carrier effect of DFT-spreading like Single Carrier - Frequency-Division Multiple Access (SC-FDMA) and solves the problem of poor peak to average power ratio in multi-carrier system . Finally, the simulation results show that this scheme can achieve the same peak to average ratio performance as SC-FDMA and effectively reduce the Bit Error Rate (BER) of the system while reducing PAPR. Moreover, this technique can greatly reduce the time overlap of signals transmitted by the system, and make the average transmitted power show almost perfect rectangular shape, but the computational complexity is only slightly increased by 2 times.