- 學位論文
Nakagami-m衰減通道之統計分析
Statistical Analysis for Nakagami-m Fading Channel Simulators
摘要
在無線環境中，衰減是多路徑傳播所造成的效應。一般都喜歡用正弦波的集合來模擬衰減效應，因為簡單明瞭。常見的衰減效應有Rayleigh、Rician、Hoyt、Nakagami-m衰減，其中Rayleigh衰減可以用Jakes所提出的模擬器來解決而延伸出來的方法也被廣泛地應用在學術研究上。以目前所遇到的衰減效應中，Nakagami-m可以運用在不同條件下之環境，可說是最具普遍性的衰減效應。所以，要如何模擬Nakagami-m衰減效應變成當前熱門的研究。模擬器常用在實驗室的原因為節省金錢和時間上的浪費。先模擬通道的特性之後，再去實際地追蹤訊號變成了模擬器最大的好處，儘管如此，很少文獻有對模擬器的統計特性作深入的研究。若從Jakes使用的模型來探討多路徑傳播之環境會發現到Jakes的模擬器並不具有衰減通道在物理上廣義穩定的特性。那麼，改進Jakes的模擬器並延伸到Nakagami-m衰減通道變成為本論文之目的。
關鍵字
衰減通道並列摘要
Fading signals due to multipath in wireless channels are widely modeled by sum-of-sinusoids-based simulator owing to simplicity and frugality. Although this calss of techniques have gained widespread acceptance, few studies apply it into the Nakagami-m fading channel.The primary reason why the Nakagami-m fading channel is getting more popular lies in its good fit for empirical data. Furthermore, the sum of the mutually exclusive Hoyt and Rician models is the Nakagami-m fading distribution. Therefore, the goal of this paper is offering a novel Nakagami-m fading simulator with its analysis of the statistical stationary squared-envelope autocorrelation function. Moreover, a modification with Walsh-Hadamard coding to the new model is also propsed to create multiple uncorrelated fading envelops.