通道模型於無線用戶迴路系統環境應用之研究

The application of channel model in wireless local loop environment

張正忠(Ching-Chung Chang)

指導教授 ： 鄭獻勳 ； 繆紹綱

中原大學/工學院/電子工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100183

摘要

在無線通訊環境中，需要一套簡便而有效率的軟體模組，以模擬電波通道傳播模式(propagation channel modeling)之接收訊號來評估訊號品質與系統效能，可提供系統業者改良無線通訊系統之服務品質。
本論文將對無線電訊號在不同環境下的傳播特性，發展出一套能對使用者所在的環境，有較強適應性的統計傳播模式，提昇系統設計者對於信號通信品質評估的正確性。在龍園地區進行實際的量測，以量測的結果來調整或修正統計傳播模式模擬上的不足，並建構可適用於有直視波(Line-of-Sight, LOS)成分的環境，符合龍園地區傳播特性的電波傳播模式。本論文將針對遠近迴響模型應用在無線用戶迴路系統環境下的傳播特性，並建立模型加以分析與比較，將模擬資料常態化(normalized)可適用於有LOS成分的環境，主要目的是在於研究實際量測資料和我們所模擬結果的差異，分別計算所模擬的平均延遲時間(mean delay)和均方根延遲時間(rms delay)兩項參數，與實際量測資料做比對，其誤差值皆小於15%，對於模擬環境有較正面的肯定。

關鍵字

傳播通道 ； 遠近迴響通道模型 ； 通道模型

並列摘要

In wireless communication environment, we need a simple and effective software propagation model that can simulate and predict the quality of received signals. The model can help to evaluate and improve the service qualities of the WCDMA/WLL systems.
　In this thesis, we conduct a series of propagation measurements at Lung-Yuan areas. Mean path loss and delay spread are measured in several selected scenarios. Then we apply the far-near echoes model to develop a statistical propagation channel that can fit use’s local environments. In addition, modeling parameters are extracted and adjusted for better prediction in the specified areas. The mean path loss and rms delay spread obtained by simulation are compared with those obtained by measurement the differences are no more than 15%. The results show good agreement between simulation and measurement data. Therefore, by using this proposed propagation channel model with appropriate model parameters, we can predict the quality and performance of the WLL system conveniently and efficiently.

並列關鍵字

propagation channel ； channel model ； far-near echoes channel model

參考文獻

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