存在CDMA干扰时超宽带系统性能分析

Performance of Ultra Wideband Systems in the Presence of CDMA Interference

超宽带系统信号功率很低,并且占用很宽的频段,系统需要与其它窄带系统共存。因此,在进行系统设计时,必须考虑窄带干扰信号对超宽带系统性能的影响。文中采用特征函数的方法精确分析了多径信道环境下,存在CDMA信号干扰时直接序列超宽带系统的性能,推导得到系统的误码率公式;最后,在基于IEEE 802.15.3 a推荐的多径信道环境下进行系统仿真和数值分析,结果表明,文中方法得到的系统性能与仿真结果基本吻合,能够较准确估计系统在存在CDMA窄带信号干扰时的性能。

The very low transmission power and the large bandwidth used, enable an UWB system to co-exist with other narrow band systems. The narrow band interference to UWB systems must be considered when DS-UWB systems are designed. In this paper, the method with characteristic function is presented for precisely calculating the bit-error probability of the DS-UWB systems in the presence of CDMA interference in a multi-path environment. In the end, the simulation tests and numerical analysis are carried out based on the IEEE 802. 15.3a channel model. The results show that the characteristic function method is accurate for predicting the BER performance of the UWB systems in the presence of CDMA inteference.