概率方法预测特定环境超宽带信号功率分布  

Prediction of power distribution of UWB signals in site-specific environment by using probabilistic methods

作　　者：扈罗全[1] 张业荣[1] 朱洪波[1] 

机构地区：[1]南京邮电大学通信与信息工程学院,江苏南京210003

出　　处：《电波科学学报》2007年第4期631-636,645,共7页Chinese Journal of Radio Science

基　　金：国家自然科学基金重点项目(No.60432040);国家自然科学基金项目(No.60572024);教育部新世纪优秀人才支持计划(No.NCET-04-0519);教育部博士点基金项目(No.200509230031)

摘　　要：针对超宽带(UWB)信号在无线信道的传播特点,使用随机桥过程产生建模UWB信号多径分量传播轨迹的随机射线,构造出可以描述UWB信道特性的基本随机变量,由此得到预测信道中某个场点接收到的信号功率的概率方法。对一个典型室内传播环境中沿着任意路径接收的UWB信号功率进行仿真计算,结果表明预测功率分布概率方法的算法稳定。对传播环境中某个区域的功率分布进行计算,同时研究了不同分集接收方式对功率预测的影响。仿真结果表明,全Rake分集接收方式并不占优势;在分集接收的抽头数较少时,部分Rake分集接收和选择性Rake分集接收方式具有相似的分集接收效果。最后对接收点信号功率的分布进行统计分析,并对概率方法与射线追踪法进行了比较。According to the propagation properties of ultra-wideband （UWB） signals in wireless channels, stochastic bridge processes are employed to generate stochastic rays, which are used to model propagation traiectories of UWB multipath components. The basic random variables describing the properties of channels are constructed, and then a probabilistic method for predicting the power distribution at some site in site-specific channel is established. The power distribution of UWB signals along an arbitrary path in indoor channels is calculated. The results demonstrate that the probabilistic algorithm is stable. The power distribution in some region in channels is simulated, and the effects on the prediction of the power distribution with different diversity methods are investigated. Simulation results indicate that there is not clear advantage in the all Rake mode; and if the tap number is small, there are similar results between the partial Rake mode and the selective Rake mode. Finally, the statistical characteristics of received power are analyzed, and the comparison between the probabilistic method and the conventional ray tracing method is carried out.

关 键 词：无线通信 超宽带 多径信道 功率覆盖 

分 类 号：TN929.5[电子电信—通信与信息系统]