增強通信性能在很大程度上取決於利用關鍵參數來適應各種無線電傳輸的環境，然而，傳統上最大概似估測(maximum likelihood estimation, MLE)需以暴力搜尋之方式找尋最佳解，以得到需要之重要參數，即都卜勒頻率(Doppler frequency)、萊斯因子(Rician factor, K factor)、和直視波之入射角(angle of arrival, AoA)。本篇論文側重於開發在萊斯衰落通道(Rician fading channel)的環境中利用接收訊號的相關特性來做參數之估測。
與傳統演算法相比，本篇論文所開發之演算法是基於時間多樣性(time diversity)下用泰勒展開式(Taylor series)以及搭配多項式回歸(polynomial regression)的方法，快速收斂所需要估測的參數。此篇論文之理論值為傳送端之參數及設定，接收端利用通道特性，以及我們設計出來之演算法，可得到所有萊斯衰落通道參數之估測值。
在效能的比較上，我們分析估測參數之均值，並使用了CRLB(Cramér-Rao lower bound)的方式去分析估測出來之均方根誤差(root mean square error, RMSE)，若和理論值距離CRLB越接近，此估測器之設計越好。

The topic of this paper is to enhance communication performance. It is depends on the use of key parameters to adapt to various radio transmission environments. Today, most of the channels from the transmitter to the receiver are violently searched for the best solution to simulate, in order to get the importance of the need. The parameters are the Doppler frequency, the Rician factor (K factor), and the angle of arrival (AoA). This paper focuses on the development with low-complexity implementation of the correlation characteristics of the received signal in the Rician fading channel and the correlation characteristics of the transmitter.
Compared with the traditional algorithm, the proposed algorithm in this paper is based on the time diversity and Taylor Series and the Polynomial Regression. The receiver only uses the channel characteristics and the algorithm we designed to get an estimated value.
In terms of performance comparison, we use Cramér-Rao lower Bound (CRLB) to analyze the estimated root mean square error (RMSE). If the estimate is closer to CRLB, the estimator is better than the traditional design.

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