蕾利衰弱通道之模擬

On the Simulation of Rayleigh Fading Channels

陳泳輝(Yung-hui Chen)

指導教授 ： 王居尉

亞洲大學/資訊學院/電腦與通訊學系碩士班/碩士(2007年)

摘要

在行動通訊領域中，無線訊號因為督卜勒位移(Doppler shift)而產生了督卜勒頻譜(Doppler Spectrum)，造成在時間軸上的相關聯，此訊號常常用蕾利分布(Rayleigh Distribution)來加以模型化。此種訊號在無線行動通訊領域的研究中扮演重要的角色
在本研究中，我們首先利用反離散傅利葉轉換(inverse discrete Fourier transform)的方法由督卜勒頻譜(Doppler spectrum)模擬時間軸上蕾利衰弱(Rayleigh Fading)之訊號。
之後我們提出由平均衰弱期間(average duration of fade, ADF)的觀念來建立有限狀態馬可夫通道(finite state Markov Channel, FSMC)模型，並用以模擬蕾利衰弱通道。我們相信提議的模擬方法可以利於未來相關無線個人通訊系統研究。

關鍵字

FSMC模式 ； 督卜勒頻譜 ； 蕾利衰減通道

並列摘要

In mobile communication, due to the Doppler shift in the receiver, the wireless signals encounter Doppler spectrum which results in the correlation in time domain. This sort of wireless signals usually are modeled as Rayleigh distributed signals and play a vital role in the researches for mobile communications.
In this research we first use the inverse discrete Fourier transform (IDFT) technique to convert the Doppler spectrum into time domain and thus product the time domain Rayleigh fading signals.
After that, we propose to establish the finite state Markov channel(FSMC) model based on the concept of average duration fade(ADF). Using this model, we may simulate the Rayleigh fading channels. We believe the simulation method may be used in the research for mobile communication.

並列關鍵字

FSMC ； Doppler spectrum ； Rayleigh fading

參考文獻

[1] John I. Smith, “A Computer Generated Multipath Fading Simulation for Mobile Radio” IEEE Trans. On Vehicular Technology vol. VT-24, no. 3, August 1975

[2] Bernard Sklar, “Rayleigh Fading Channels in Mobile Digital Communication Systems PartI : Characterization” IEEE Communication Magazine pp,90–100 July 1997

[3] Bernard Sklar, “Rayleigh Fading Channels in Mobile Digital Communication Systems Part II : Mitigation” IEEE Communication Magazine pp,102–109 July 1997

[4] P. Dent, G. E. Bottomely, and T.Croft, “Jakes Fading Model Revisited” Electronics Letters 24th June 1993 vol.29 no.13 pp.1162–1163

[5] Hong Shen Wang, and Nader Moayeri, “Finite-State Markov Channel—A useful Model for Radio Communication Channels” IEEE Trans. On Vehicular Technology vol.44, No. 1,pp. 163–171, February 1995