長期演進系統中利用聯合最大機率估測法提升定位精準度之研究與實現

Research and Implementation of Positioning Accuracy Improvement by Joint Maximum Likelihood Estimation in the LTE system

江禾才(Ho-Tsai Chiang)

指導教授 ： 謝欣霖

國立臺北大學/電機資訊學院/通訊工程研究所/碩士(2016年)

摘要

近來，許多新服務都要求更高的定位精準度，而3GPP也計畫增進現有定位技術以滿足這些需求。在此研究中，我們提出了兩種方式去改善在現有長期演進系統中定位技術的精準度。首先，我們探討定位精準度的升取(oversampling)效應。藉由四倍接收波型的升取樣，多通道的估測可以得到較精準的結果呈現。藉由對現有技術加入升取樣，我們觀察到定位精準度的提升。第二個方式為將通道估測器由一個簡易但有效的通道估測演算法替代。我們使用聯合最大機率通道估測器(joint maximum-likelihood channel estimator)以提升多通道延遲估測的精準度，並得到更精準的定位估測。我們的所有模擬皆遵守3GPP規範以保證所得之定位精準度增益符合現實通訊系統。

關鍵字

升取樣

並列摘要

Recently, many new services demand higher positioning accuracy and 3GPP has made the plan to enhance the existing position technique to fulfill those requirements. In this work, we propose two methods to improve the accuracy for the existing position technology of LTE. First, we investigate the effect of oversampling to the position accuracy. By four times oversampling the received waveform, the multipath channel estimation and the subsequent reporting can be more accurate. We then observe the positioning accuracy improvement for the existing technique due to oversampling. Secondly, the channel estimator is replaced by a simple yet power channel estimation algorithm. The joint maximum likelihood channel estimator improves the multipath delay estimation accuracy so that more accurate position estimation is resulted. We perform all simulations following the 3GPP standards to justify the position accuracy enhancement of the LTE system.

並列關鍵字

Oversampling

參考文獻

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