【正文】
Title: Analysing the model and simulation of the channel in mobile munication Abstract The research on simulation model of mobile channel has developed for a long time, but most of them only consider Small Scale Fading. While, for the research of Cognitive Radio, the most basic task is to resolve the signal apperception through air interface, while not only solve the influence of Small Scale Fading on data transfer technology. Cognitive Radio also need to estimate whether the accessing of unlicensed subscribers bring interference to licensed work and its subscribers and the grade of that interference. As thus, Cognitive Radio is able to give a mechanism of the intellectualized login and logout for unlicensed subscribers. It will also give a judge and calculate method for the threshold value of login and logout. So, in this paper, Large Scale Fading and Small Scale Fading are both considered in the research of simulation model of mobile channel. This paper reviews the history of personal mobile munication about forty years since it came into business. Then remends the status quo of research on simulation of radio channel and analyses the basic performance of radio channel fading from the point of view of Small Scale Fading and Large Scale Fading. Keywords: Rayleigh Channel, FrequencySelective Fading Channel, Line of Sight, NonLine of Sight, Path Loss, Simulation 目錄 第 1 章 緒論 ................................................................................................................... 5 移動(dòng)通信的發(fā)展 ................................................................................................... 5 移動(dòng)通信的發(fā)展?fàn)顩r .................................................................................. 5 移動(dòng)通信技術(shù)的發(fā)展 .................................................................................. 5 認(rèn)知無線電的概述 ............................................................................................... 8 信道仿真技術(shù)的發(fā)展及現(xiàn)狀 ................................................................................. 8 無線信道仿真的意義 .......................................................................................... 10 第 2 章移動(dòng)信道傳播特性 ............................................................................................... 11 大尺度衰落 ........................................................................................................ 12 自由空間傳 播模型 .................................................................................... 12 小尺度衰落 ........................................................................................................ 14 衰落和多徑 .............................................................................................. 14 小尺度衰落的兩種機(jī)理 ............................................................................. 15 小尺度衰落信道的分類 ............................................................................. 16 第三章 移動(dòng)信道分析模型的建立和統(tǒng)計(jì)特性的研究 ....................................................... 18 衰落信號(hào)分析模型的建立 ................................................................................... 18 Rayleigh 過程 ............................................................................................ 18 對(duì)數(shù)正態(tài)過程 ........................................................................................... 19 多普勒功率譜密度函數(shù) ...................................................................................... 21 Jakes 功率譜密度函數(shù) ............................................................................ 21 Gaussian 功率譜密度函數(shù) .......................................................................... 22 信道分析模型的統(tǒng)計(jì)特性 ................................................................................... 22 Rayleigh 過程 ............................................................................................ 23 Suzuki 過程 ............................................................................................... 23 第四章 移動(dòng)信道仿真模型的建立和分析 ........................................................................ 26 移動(dòng)信道的確定性仿真模型的建立 ..................................................................... 27 仿真系統(tǒng)的組成 ....................................................................................... 27 仿真系統(tǒng)參數(shù)的計(jì)算方法 ......................................................................... 29 仿真結(jié)果分析 .................................................................................................... 31 頻率選擇性衰落信道模型的建立 ........................................................................ 33 致謝 ............................................................................................................................... 35 參考文獻(xiàn) ........................................................................................................................ 36 第 1 章 緒論 通信技術(shù)經(jīng)歷了從有線到無線、從模擬到數(shù)字兩次根本性地變革。 2020屆畢業(yè)生 畢業(yè)論文 題 目: 移動(dòng)通信 系統(tǒng)中 信道建模與仿真 研究 院系名稱: 信息 工程學(xué)院 專業(yè)班級(jí): 電子信息工程 學(xué)生姓名: 學(xué) 號(hào) : 指導(dǎo)教師: 教師職稱: 教授 2020 年 6 月 2 日 摘要 業(yè) 界對(duì) 移動(dòng) 信道仿真模型的研究由來已久,但多數(shù)只考慮了小尺度衰落,而對(duì)于認(rèn)知無線電的研究來說,不單單需要解決小尺度衰落對(duì)數(shù)字傳輸技術(shù)的影響,最基礎(chǔ)的是要解決認(rèn)知無線電在空中接口上對(duì)信息的感知,并且要根據(jù)感知的信號(hào)強(qiáng)度判斷非授權(quán)用戶的接入是否會(huì)對(duì)授權(quán)網(wǎng)絡(luò)用戶造成干擾以及干擾的程度,進(jìn)而提出非授權(quán)網(wǎng)絡(luò)用戶智能接入和退出 的機(jī)制以及接入和退出閾值的判斷和計(jì)算,這勢(shì)必要涉及到大尺度衰落,所以本課題在研究移動(dòng) 信道仿真建模時(shí)同時(shí)考慮了大尺度衰落和小尺度衰落。 本文回顧了移動(dòng)通信商用以來近 40 年的發(fā)展和演進(jìn)的歷史,介紹了 移動(dòng) 無線信道仿真研究的現(xiàn)狀,分別從小尺度衰落和大尺度衰落的角度分析了無線信道衰落的基本特性。自從 1894年馬可尼第一次用無線電實(shí)現(xiàn)與橫跨英吉利海峽的船舶之間的通信以來,經(jīng)過了數(shù)十年的發(fā)展,直到 20 世紀(jì) 70 年代才實(shí)現(xiàn)了提供個(gè)人無線通信服務(wù)。 移動(dòng)通信的發(fā)展 移動(dòng)通信的發(fā)展?fàn)顩r 到目前為止,已商用的移動(dòng)通信從第一代到第三代的發(fā)展如下圖所示: 圖 11 移動(dòng)通信系統(tǒng)發(fā)展過程 移動(dòng)通信技術(shù)的發(fā)展 ( 1G)移動(dòng)通信技術(shù) 人們習(xí)慣于將模擬蜂窩系統(tǒng)稱為第一代移動(dòng)通信系統(tǒng),美國(guó)是率先開發(fā)模擬蜂窩系統(tǒng)的國(guó)家之一,主要有 AMPS 和 ARTS 系統(tǒng),分別于 1983 年 10 月和 1984年初投入運(yùn)營(yíng)。北歐四國(guó)開發(fā)的 NMT450移動(dòng)電話系統(tǒng)于 19