无线通信原理清晰版

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1．无线信道...................................................................1
1．1自由空间无线电波传播..................................................................................................1
1．2移动通信的电波传播特点..............................................................................................1
1．3移动通信电波传播特性..................................................................................................2
1．3．1短期（快）衰落................................................................................................3
1．3．2长期（慢）衰落................................................................................................6
1．3．3衰落特性............................................................................................................6
1．4电波传播损耗预测模型..................................................................................................6
1．4．1 Okumura-Hata模型............................................................................................7
1．4．2 COST231 Walfisch-Ikegami模型......................................................................9
1．5覆盖设计........................................................................................................................10
1．5．1传播模型的选用及修正..................................................................................11
1．5．1基站覆盖预测..................................................................................................11
1．5．3功率控制..........................................................................................................14
2．分集技术.................................................................15
2．1分集技术的概念............................................................................................................15
2．2分集技术的分类............................................................................................................15
2．3显分集技术....................................................................................................................15
2．3．1空间分集..........................................................................................................15
2．3．2极化分集..........................................................................................................16
2．4显分集的合并技术........................................................................................................18
2．4．1信号合并准则..................................................................................................18
2．4．2最大信噪比准则下的信号合并方法..............................................................18
2．5隐分集技术....................................................................................................................19
3．无线通信多址技术.................................................21
3．1 多址技术概述...............................................................................................................21
3．2 频分多址.......................................................................................................................21
3．3 时分多址.......................................................................................................................22
3．4 码分多址.......................................................................................................................22
3．5 扩频技术.......................................................................................................................25
3．6 空分多址.......................................................................................................................27
4．无线通信中的资源分配原理及算法举例.............31
4．1蜂窝的概念....................................................................................................................31
4．2以GSM为例介绍FCA...................................................................................................31
4．3 PHS无线市话的频率使用............................................................................................33
4．3．1频率分配..........................................................................................................33
4．3．2 PHS 频率指配................................................................................................35
4．4多信道共用技术............................................................................................................35
4．5微蜂窝与信道动态分配技术........................................................................................38
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无线通信原理
5．语音编码技术.........................................................41
5．1概述................................................................................................................................41
5．2 脉冲编码调制...............................................................................................................43
5．2．1 脉冲编码调制（PCM）技术........................................................................43
5．2．2自适应差分脉冲编码调制(ADPCM).............................................................48
6．PHS通信系统中的基本调制技术..........................51
6．1调制技术概述................................................................................................................51
6．2 π/4-QPSK调制...............................................................................................................52
6．3 衰落和干扰中π/4-DQPSK的性能.............................................................................53
7．天线.........................................................................56
7．1 天线电指标的定义.......................................................................................................56
7．2 天线的高度和间距.......................................................................................................59
7．3 PAS天线选择.................................................................................................................60
7．4 ZXPCS基站天线说明...................................................................................................62
7．4．1 天线电性能技术指标.....................................................................................62
7．4．2 天线环境性能指标.........................................................................................63
8．OSI 7层结构简介...................................................65
8．1物理层............................................................................................................................66
8．2数据链路层....................................................................................................................67
8．3网络层............................................................................................................................68
8．4 PHS空中接口协议栈....................................................................................................69
附录...............................................................................71
1．双共技术...........................................................................................................................71
2．单位换算...........................................................................................................................71
3．缩略语...............................................................................................................................72