The Investigation of MC-CDMA Systems in FBS Environment with Fading Channels 謝孟村、陳雍宗
E-mail: 9805883@mail.dyu.edu.tw
ABSTRACT
In this paper, the impact of the correlation on the performance of multiple-cell MC-CDMA (multiple-cell codel-division
multiple-access) cellular systems in FBS(further base station) environment with fading channels is investigated. A new closed-form formula for the joint probability density function (joint pdf) of the diversity combiner with arbitrary correlation coefficients in terms of the generalized Laguere polynomial and new expressions of average bit-error rate (BER) for the MC-CDMA system are given in this paper. The results demonstrate that the BER is significantly dependent on the correlation characteristic of diversity branching for multiple-cell environments.
Keywords : Laguerre polynomial、multiple-cell、correlated Nakagami-m fading、MC-CDMA system Table of Contents
第一章 緒論．．．．．．．．．．．．．．．．．．．．．．．1 1.1 研究動機與目的．．．．．．．．．．．．．．．．1
1.2 論文綱要．．．．．．．．．．．．．．．．．．．3
第二章 訊號衰落．．．．．．．．．．．．．．．．．．．．．5 2.1 訊號衰落的介紹．．．．．．．．．．．．．．．．5
2.2 電波傳輸現象．．．．．．．．．．．．．．．．．6 2.2.1反射．．．．．．．．．．．．．．．．．．7 2.2.2繞射．．．．．．．．．．．．．．．．．．7 2.2.3散射．．．．．．．．．．．．．．．．．．7 2.3 衰落的分類．．．．．．．．．．．．．．．．．．8 2.3.1 大尺度衰落．．．．．．．．．．．．．．．9 2.3.1.1 路徑損耗．．．．．．．．．．．．．9 2.3.1.2 遮蔽效應．．．．．．．．．．．．13 2.3.2 小尺度衰落．．．．．．．．．．．．．．．13 2.3.2.1 時間延遲擴散．．．．．．．．．．15 2.3.2.2 時域上的變動性．．．．．．．．．17
2.4 多重路徑及多重衰落簡介．．．．．．．．．．．19 2.5 多重路徑衰落所造成的效應．．．．．．．．．．19 2.6 衰落通道的數學模型．．．．．．．．．．．．．20 2.7 常用通信波道統計分佈介紹與比較．．．．．．．23 2.7.1 Normal(Gaussian)衰落分佈．．．．．．．．23 2.7.2 Rayleigh衰落分佈．．．．．．．．．．．．26 2.7.3 Rician衰落分佈．．．．．．．．．．．．29 2.7.4 Nakagami衰落分佈．．．．．．．．．．．34
第三章 CDMA系統簡介．．．．．．．．．．．．．．．．．38 3.1 前言．．．．．．．．．．．．．．．．．．．．38
3.2 DS-CDMA系統．．．．．．．．．．． ．．．．38 3.3 MC-CDMA系統．．．．．．． ．．．．．．．40 3.4 Multicarrier (MC)-DS-CDMA系統．．．．．．．．43 3.5 Multi-tone(MT)-CDMA系統．．．．．．．．．．45
第四章 分集合成技術．．．．．．．．．．．．．．．．．．48 4.1 系統模式．．．．．．．．．．．．．．．．．．48
4.1.1極化分集．．．．．．．．．．．．．．．49 4.1.2 頻率分集．．．．．．．．．．．．．．．50
4.1.2.1 選擇性合成．．．．．．．．．．．．51 4.1.2.2 最大比例合成．．．．．．．．．．．52 4.1.3 空間分集．．．．．．．．．．．．．．．．54 4.1.4 時間分集．．．．．．．．．．．．．．．．55
第五章 多蜂巢 MC-CDMA 系統於Nakagami-m 衰落之分析．57 5.1 系統模式．．．．．．．．．．．．．．．．．．57 5.1.1 發射機模式．．．．．．．．．．．．．．．57 5.1.2 接收機與通道模式．．．．．．．．．．．．58 5.2 決策變數之統計特性．．．．．．．．．．．．．59 5.3 聯合pdf之計算．．．．．．．．．．．．．．．．60 5.4 數值分析結果與討論．．．．．．．．．．．．．61
第六章 結論．．．．．．．．．．．．．．．．．．．．．．66 參考文獻．．．．．．．．．．．．．．．．．．．．．．．．67 附 錄．．．．．．．．．．．．．．．．．．．．．．．．．69 REFERENCES
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