Study on Analysis of Multipath Propagation for Indoor Radio Digital Communications

室内无线数字通信多径传播分析研究

基本信息

批准号：
04650342
负责人：
INAGAKI Naoki
金额：
$ 1.28万
依托单位：
Nagoya Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1993
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04650342/
关键词：
Indoor radio communication Multipath propagation MUSIC algorithm ESPRIT algorithm Estimation of direction of arrival Estimation of delay time Diversity reception Adaptive filtering 多重波伝搬構造高分解能近傍波源

项目摘要

The idea of implementing indoor radio communication systems is so attractive because of high mobility and no trouble in wiring. However, indoor radio multipath propagation environments limit the design of these systems. Therefore, this project of research is concerned with clarifying the characteristics of indoor radio propagation. For this pupose, it is most effective to estimate the directions of arrival and delay times of multipath waves. So far, we proposed and developed a method of estimating the directions of arrival and delay times. This method utilized the MUSIC or ESPRIT algorithms which are spectrum analysis techniques with high resolution property. During 1992 and 1993, we continued to improve the estimation method through computer simulation and indoor experiments. The results obtained are described below.1. First, we proposed a method of simultaneously estimating both the directions of arrival and delay times of multipath waves. The great advantage of this method is that w … More e can easily identify the propagation paths of incident waves based on the estimation results. In addition to computer simulation, we carried out experiments in a limited region. From the estimation results, we recongnized 5 to 10 significant waves, the directions of which are almost uniformly distributed in space and also the delay times of which are less than 50 ns. These results demonstrated the indoor radio environments are much complicated. Thus, we confirmed that diversity reception, especially the directivity diversity, is much effective for indoor radio communication systems under multipath propagation environments.2. The proposed method has great capability of classifying the multipath waves in terms of directions of arrival and propagation delay times. For the arriving waves with the low signal-to-noise ratio (SNR), however, it has some errors in the estimates of delay times and directions of arrival. Therefore, we further presented a technique of applying an adaptive(optimum) filtering to the MUSIC or ESPRIT estimator to enhance the estimation accuracy. The principle of our adaptive filtering is based on the directionally constrained adaptive array. Via computer simulation, we showed that the presented algorithm is more effective in multipath environments of the low SNR. Less

实现室内无线电通信系统的想法非常有吸引力，因为它具有高移动性且没有布线麻烦，但是室内无线电多路径传播环境限制了这些系统的设计，因此，本研究项目旨在阐明室内无线电通信系统的特性。为此，估计多径波的到达方向和延迟时间是最有效的，我们提出并开发了一种利用 MUSIC 或 MUSIC 来估计到达方向和延迟时间的方法。 ESPRIT 算法1．在1992年和1993年期间，我们通过计算机模拟和室内实验不断改进了估计方法。首先，我们提出了一种同时估计两个方向的方法。该方法的最大优点是可以根据估计结果轻松识别入射波的传播路径。除了计算机模拟外，我们还在有限的区域内进行了实验。估计结果，我们识别出5到10个有效波，其方向在空间上几乎均匀分布，并且延迟时间小于50纳秒。这些结果表明室内无线电环境非常复杂，因此我们证实了分集接收，尤其是方向性分集，对于多径传播环境下的室内无线通信系统非常有效。2．然而，它在延迟时间和到达方向的估计中存在一些误差，因此，我们进一步提出了一种对 MUSIC 或 ESPRIT 估计器应用自适应（最优）滤波的技术来增强。我们的自适应滤波的原理是基于方向约束的自适应阵列，通过计算机仿真，我们表明该算法在低信噪比的多径环境中更有效。