降低FBMC-OQAM峰均值比的低复杂度PTS算法

PTS algorithm with low complexity for reducing PAPR of FBMC-OQAM

针对滤波器组多载波/正交幅度调制(FBMC-OQAM)系统中,功率峰均值比(PAPR)过高且传统抑制方法复杂度过高难以实现的问题,提出了一种应用在FBMC-OQAM系统中的新的抑制方法。首先,在传统部分传输序列(PTS)方法的基础上根据系统特性进行改进,得到迭代PTS(IPTS)算法,较传统PTS算法计算复杂度有明显降低;其次,将IPTS算法与限幅(Clipping)算法相结合,作为一种新的IPTS-Clipping联合算法应用在FBMC-OQAM系统中,该算法先利用IPTS算法对FBMC信号进行处理,再利用限幅方法进一步抑制系统的PAPR。理论分析和仿真实验结果表明,与传统PTS算法相比,所提算法减少了约70%的计算次数,当累计分布函数CCDF为10-3时,所提算法的PAPR值较原始信号降低了约48.5%,较PTS算法降低了33%,抑制效果明显优于其他方法。所提算法不仅能够显著抑制FBMC系统的PAPR,同时复杂度远低于其他原始算法,具有十分良好的性能。

Aiming at the problem that the Peak-to-Average Power Ratio （PAPR） is too high and the complexity of the traditional suppression method is too high for the Filter Bank MultiCarrier/Offset Quadrature Amplitude Modulation （FBMC-OQAM） system, a new method of suppressing in FBMC-OQAM system was proposed. Firstly, based on the traditional Partial Transmit Sequence （PTS） method, the system characteristics have been improved, the Iterative PTS （IPTS） algorithm was obtained, which complexity was significantly lower than that of the traditional PTS algorithm. Secondly, the IPTS algorithm and the Clipping algorithm were used as a new IPTS-Clipping joint algorithm in FBMC-OQAM system. The FBMC signal was processed by the IPTS algorithm and then the clipping method was used to further suppress the PAPR of the system. The results of theoretical analysis and simulation show that compared with the traditional PTS algorithm, the proposed algorithm reduces the number of calculations by about 70%. When the cumulative distribution function CCDF reaches 10-3, the PAPR value of the proposed algorithm is 48.5%, lower than that of the original signal, and 33% lower than that of PTS. The suppression effect is obviously better than other methods. The proposed algorithm not only can significantly suppress the PAPR of FBMC system, but also has much lower complexity than other original algorithms.