为了提高超宽带多址系统的误码性能,提出了一种分数傅里叶变换域的超宽带多址方式,与时分多址相结合,将相位的变化引入到脉冲波形的选择中来.设计了一组正交性较好的脉冲波形,将其应用于超宽带系统中.利用所采用波形在某一阶分数傅里叶变换域发生能量相对聚集的特性,在分数傅里叶变换域进行滤波降低多址干扰.仿真结果表明,文中所采用的多址方式有效地提高了系统的容量,各用户间正交性较好,分数傅里叶变换域滤波可以提高系统的误码性能.

Proposed in this paper is a multiple access scheme based on fractional Fourier transform（FrFT） to improve the bit error rate（BER） performance of ultra-wideband（UWB） system.In this scheme,with the combination of TDMA（Time Division Multiple Access） and the utilization of phase change in waveform selection,a set of orthogonal pulse waveforms are designed and applied to the ultra-wideband system.Then,based on the energy-aggregating characteristics of the signal in the order-FrFT domain,filtering is conducted to reduce the multiple access interference.Simulated results indicate that the proposed scheme effectively improves the system capacity and the orthogonality among pulse waveforms,and that the filtering in FrFT domain further improves the BER perfor-mance of the system.