差分相位鍵移收發機與行動通道模擬器之數位信號處理實作

DSP Implementation of DPSK Transceiver and Mobile Channel Simulator

簡志達(Chih-Ta Chien)

指導教授 ： 林丁丙

國立臺北科技大學/機電學院/電腦與通訊研究所/碩士(2005年)

https://doi.org/10.6841/NTUT.2005.00035

摘要

電波傳播通道的研究與模式化是分析與評估無線通訊系統不可或缺的工作，針對此需求，本論文首先探討如何利用弦波相加法(Rice’s Sum of sinusoids)，合成彩色高斯隨機程序，使得經由彩色高斯隨機程序所合成的通道能與實際通道之時間選擇性之統計特性相符合。此外，本論文有別於前人所提出的查表法(Multi-Table Look-Up)，我們將其進一步改進為利用單一表單(Signal Table)進行查表動作，並分析其複雜度，此一改進將使得在通道模擬當中能夠動態調整都卜勒頻率，而有助對於無線通訊系統在不同都卜勒頻率影響下的效能分析。
再者，本論文將無線通訊架構分三部份(傳送端、接收端以及通道)以數位信號處理器實現，此部份工作將著重於同步問題的解決，在本論文我們將同步問題的解決方案大致分為三個部份1.)以封包為傳送單位的機制下如何準確的偵測出封包起點2.)傳送機或接收機的開機先後順序以及3.)當有時序延遲時對同步所帶來的影響，在解決同步問題之後我們分析位元錯誤率以驗證通道正確性。
最後，我們將以語音當傳送信號，送入此通訊架構並動態的改變都卜勒頻率後對其結果的展示。

關鍵字

時間選擇性衰落 ； 弦波相加法 ； 高斯隨機程序 ； 都卜勒頻率

並列摘要

The research and simulation modeling on wireless fading channel is indispensable to analyze and evaluate the performance for mobile communication. For this need, a color Gaussian random processes which are synthesized by the sum of sinusoids will be discussed firstly in this thesis. And the time selective statistical characteristics of channel synthesized by color Gaussian random processes and practical fading channel can be matched. In this thesis, a modificatory method which using single table for table look-up will be proposed which is unlike multiple-table look-up method which is proposed in literature. And then, we take advantage of this method to analyze the complexity. Due to this improvement the Doppler frequency can be changed dynamically in channel simulation and it can be conductive to the performance analysis for wireless communication system under different Doppler frequencies.
Furthermore this thesis separates the wireless framework into three parts (transmitter, receiver and channel) and each part achieves by using digital signal processor. The point of this work is to solve the synchronization problem. For this problem we separate into three issues. 1.) How to estimate the packet start exactly when under the packet transmission scheme. 2.) The effect of synchronization problem causes by the priority which transmitter and receiver power on and 3.) the timing delay. After solved the synchronization problem we analysis the BER for verifying accuracy of channel.
At last, the result of the output audio signals caused by inputting radio signals and dynamically changing the Doppler frequency will be shown.

並列關鍵字

Time selective fading ； Sum of sinusoids ； Gaussian random processes ； Doppler Frequency

參考文獻

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