室内环境信息对射线跟踪算法预测精度的影响研究

发布时间：2018-06-26 02:58

本文选题：几何误差 + 电参数误差　；参考：《西安电子科技大学》2014年硕士论文

【摘要】：移动通信技术的飞速发展带动了室内微微小区场景下无线网络设备市场的快速壮大。这种背景下一个能够精确预测室内环境下的传播信道特性的传播模型就显得极其重要。传统的传播模型通常都是基于经验模型和半经验模型,然而随着移动通信技术在室内场景下的快速发展和大规模商用,传统的传播模型由于其自身的局限性已不能胜任提供准确的传播预测的要求。射线跟踪技术在对无线通信信道进行定点预测时能够计算多径接收情况下的时延和到达角信息,能够解决传统模型预测精度不达标的问题,因此,射线跟踪技术能为无线信道传播特性研究和网络规划提供可靠的理论依据。本文针对复杂室内微微小区场景下的环境信息,设计了一种几何信息和材料电参数信息存储格式,能够对室内环境信息进行准确的建模。在此基础上使用射线跟踪技术对室内场景下的无线信道特征进行预测。本文系统地研究了室内场景下几何信息建模误差、材料信息建模误差以及收、发天线极化方式对射线跟踪算法预测精度的影响研究。主要的研究内容及取得的研究成果如下:1.系统讲解了射线跟踪算法的理论基础:几何光学理论以及一致性几何绕射理论;详细给出了本文中使用射线跟踪模型需要进行预测的无线信道参数及其相应的计算公式。阐述了室内场景下射线跟踪算法中几种射线路径的寻找,并给出了使用三维射线跟踪模型进行室内电波传播特性预测研究的操作步骤。2.针对室内环境中几何信息特征,使用两种方式来人为生成带有几何信息误差的地图,使用射线跟踪算法在这些误差地图上预测视距路径、非视距路径以及预测平面上的接收功率和均方根时延扩展值,并与标准地图进行对比进而分析几何信息建模误差对射线跟踪预测精度的影响。3.针对室内环境中材料信息特征,分别研究相对介电常数和电导率建模误差对射线跟踪预测精度的影响。在建模过程中针对室内天花板、地板、四周墙壁以及室内物体分别生成误差地图,使用射线跟踪算法在这些误差地图上预测视距路径、非视距路径以及预测平面上的接收功率和均方根时延扩展值,并与标准地图进行对比进而分析材料信息建模误差对射线跟踪预测精度的影响。4.研究了收、发天线极化方式对射线跟踪预测精度的影响。在研究过程中设置收、发天线阵列阵面是否对齐,考虑接收天线是否位于发射天线视距路径上,并且收、发天线采用两组同极化方式和两组交叉极化方式,在以上情形下研究收、发天线不同极化方式对射线跟踪预测结果的影响。
[Abstract]:With the rapid development of mobile communication technology, the wireless network equipment market grows rapidly in the scene of indoor picoculture. In this context, a propagation model which can accurately predict the characteristics of propagation channel in indoor environment is very important. Traditional communication models are usually based on empirical models and semi-empirical models. However, with the rapid development of mobile communication technology in indoor scenarios and large-scale commercial, Because of its own limitations, the traditional communication model can not meet the requirements of accurate propagation prediction. The ray-tracing technique can calculate the time delay and angle of arrival information in the case of multipath reception in the fixed-point prediction of wireless communication channel, and can solve the problem that the prediction accuracy of the traditional model is not up to the standard. The ray tracing technology can provide reliable theoretical basis for the research of wireless channel propagation characteristics and network planning. In this paper, a storage format of geometric information and material electrical parameter information is designed for the environment information in the complex indoor picocell scene, which can accurately model the indoor environment information. Based on this, ray tracking technology is used to predict the wireless channel features in indoor scenes. In this paper, the effects of geometric information modeling error, material information modeling error and polarization mode of receiving and transmitting antenna on the prediction accuracy of ray tracking algorithm are studied systematically. The main contents and results of the research are as follows: 1. The theoretical basis of ray tracking algorithm, geometric optics theory and consistent geometric diffraction theory, are systematically explained, and the parameters of wireless channel and their corresponding calculation formulas are given in detail in this paper, which need to be predicted by ray tracking model. In this paper, the search of several ray paths in the ray tracing algorithm in indoor scene is described, and the operational steps of predicting the propagation characteristics of indoor radio waves by using the three-dimensional ray tracing model are given. Aiming at geometric information features in indoor environment, two methods are used to artificially generate maps with geometric information errors, and ray-tracing algorithms are used to predict line-of-sight paths on these error maps. The non-line-of-sight path, the received power and the root mean square delay spread in the prediction plane are compared with the standard map, and the effect of geometric information modeling error on the prediction accuracy of ray tracking is analyzed. The effects of relative dielectric constant and conductivity modeling error on the precision of ray tracking prediction were studied according to the information characteristics of materials in indoor environment. In the process of modeling, error maps are generated for indoor ceilings, floors, surrounding walls and indoor objects respectively, and ray tracing algorithm is used to predict the distance of sight path on these error maps. The non-line-of-sight path, the received power and the root mean square delay spread on the prediction plane are compared with the standard map, and the influence of modeling error of material information on the prediction accuracy of ray tracking is analyzed. The effect of polarization mode of receiving and transmitting antenna on the precision of ray tracking prediction is studied. In the course of the research, whether the antenna array is aligned or not, considering whether the receiving antenna is located on the transmission antenna's line-of-sight path, and receiving, the antenna adopts two groups of identical polarization mode and two groups of cross-polarization mode. In the above case, the effects of different polarization modes of receiving and transmitting antennas on the prediction results of ray tracking are studied.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.5

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