樊昌信通信原理考研真题题库视频网课！
<p class="ne-p"><strong><span class="ne-text">樊昌信通信原理考研真题题库视频网课</span></strong><strong><span class="ne-text">！</span></strong></p><p class="ne-p"><strong><span class="ne-text">资料全称：</span></strong><strong><span class="ne-text">樊昌信《通信原理》（第7版）全套资料【笔记＋题库】</span></strong></p><p class="ne-p"><strong><span class="ne-text">樊昌信通信原理考研真题题库视频网课</span></strong><strong><span class="ne-text">部分摘录：</span></strong></p><p class="ne-p"><strong><span class="ne-text">室带高斯噪声的包络服从（）分布，而同相分量则服从（）分布。[南邮20102009研]</span></strong></p><p class="ne-p"><span class="ne-text">A.均匀；正态</span></p><p class="ne-p"><span class="ne-text">B.瑞利；高斯</span></p><p class="ne-p"><span class="ne-text">C.均匀；瑞利</span></p><p class="ne-p"><span class="ne-text">D.不确定</span></p><p class="ne-p"><span class="ne-text">【答案】B</span></p><p class="ne-p"><span class="ne-text">【解析】窄带高斯曝声的相位服从均匀分布；其分布同相分量和正交分量皆为高斯过程。</span></p><p class="ne-p"><strong><span class="ne-text">下列选项中（）与无线通信中的多径现象无关。[南邮2010、2009研]</span></strong></p><p class="ne-p"><span class="ne-text">A.码间干扰</span></p><p class="ne-p"><span class="ne-text">B.门限效应</span></p><p class="ne-p"><span class="ne-text">C.频率选择性衰落</span></p><p class="ne-p"><span class="ne-text">D.瑞利衰落</span></p><p class="ne-p"><span class="ne-text">【答案】B</span></p><p class="ne-p"><span class="ne-text">【解析】多径效应由信道的时间色散引起：信号经过反射、散射等不同路径的传输，于不同的时刻到达接收端，从而形成多径效应。①多径效应会使数字信号的码间串扰增大。②多径时域上的色散在频域上表现为相干带宽，即会产生频率选择性衰落。③在无线通信信道环境中，电磁波经过反射、折射、散射等多条路径传播到达接收机后，总信号的强度服从瑞利分布。同时由于接收机的移动及其他原因，信号强度和相位等特性又在起伏变化，故称为瑞利衰落。因此，瑞利衰落与多径有关。当输入信噪比低于一定数值时，解调器输出信曝比急剧恶化，这种现象称为门限效应，与多径现象无关。</span></p><p class="ne-p imgbox"><span class="image-box"><img data-original="http://image.uc.cn/s/wemedia/s/upload/2022/260cafb3a8d6f83126ca7d60f1540a94.png" data-src="http://image.uc.cn/o/wemedia/s/upload/2022/260cafb3a8d6f83126ca7d60f1540a94.png;,4,png;3,700x.png" src="//image.uc.cn/s/uae/g/1v/images/image-lazyload.png" uploaded="1" data-infoed="1" data-width="775" data-height="586" data-format="png" data-size="543888000" data-index="0" class="image-default-bg image-loaded b-lazy" style="width: 700px !important; height: 529.29px !important;" heavypress="http://image.uc.cn/o/wemedia/s/upload/2022/260cafb3a8d6f83126ca7d60f1540a94.png;,4,png;3,700x.png"><span class="share-import-title"></span></span></p><p class="imgbox_desc"><span>樊昌信通信原理考研真题题库视频网课！</span></p><p class="ne-p"><strong><span class="ne-text">AM信号中载波功率（）用户信息，边带功率（）用户信息。[南邮2010研]</span></strong></p><p class="ne-p"><span class="ne-text">A.承载，承载</span></p><p class="ne-p"><span class="ne-text">B.不承载，不承载</span></p><p class="ne-p"><span class="ne-text">C.承载，不承载</span></p><p class="ne-p"><span class="ne-text">D.不承载，承载</span></p><p class="ne-p"><span class="ne-text">【答案】D</span></p><p class="ne-p"><span class="ne-text">【解析】一个已调波由载波和边带组成，而处于载波两边的频谱（代表信息），被称为边带，它们的功率叫做边带功率；而载波功率不承载任何用户信息。</span></p><p class="ne-p"><strong><span class="ne-text">下列模拟通信系统中存在门限效应的是（）。[南邮2009研]</span></strong></p><p class="ne-p"><span class="ne-text">A.相干AM</span></p><p class="ne-p"><span class="ne-text">B.DSB</span></p><p class="ne-p"><span class="ne-text">C.FM</span></p><p class="ne-p"><span class="ne-text">D.VSB</span></p><p class="ne-p"><span class="ne-text">【答案】C</span></p><p class="ne-p"><span class="ne-text">【解析】用相干解调的方法解调各种线性调制信号时不存在门限效应。</span></p><p class="ne-p"><strong><span class="ne-text">下列模拟通信系统中目前在广播中还在广泛使用的是（）。[南邮2010研]</span></strong></p><p class="ne-p"><span class="ne-text">A.相干AM</span></p><p class="ne-p"><span class="ne-text">B.DSB</span></p><p class="ne-p"><span class="ne-text">C.FM</span></p><p class="ne-p"><span class="ne-text">D.VSB</span></p><p class="ne-p"><span class="ne-text">【答案】C</span></p><p class="ne-p"><span class="ne-text">【解析】FM调制系统以牺牲带竞来换取高的抗噪能力，由于该系统的可靠性好，因而在高逼真度音乐广播系统及发射功率有限的点对点通信系统中广泛应用调频模式。</span></p><p class="ne-p"><strong><span class="ne-text">数字基带信号的功率谱密度一般包括两部分（）和（）。[南邮2009研]</span></strong></p><p class="ne-p"><span class="ne-text">A.离散谱，线谱</span></p><p class="ne-p"><span class="ne-text">B.广义谱，谐线</span></p><p class="ne-p"><span class="ne-text">C.离散谱，连续谱</span></p><p class="ne-p"><span class="ne-text">D.连续谱，光谱</span></p><p class="ne-p"><span class="ne-text">【答案】C</span></p><p class="ne-p"><span class="ne-text">【解析】数字基带信号的功率谱密度一般包括两部分：连续谱和离散线谱。连续谱取决于单个脉冲波形的频谱；离散线谱取决于单极性基带信号矩形脉冲的占空比。</span></p><p class="ne-p"><strong><span class="ne-text">MSK信号不但（）连续，而且（）连续，故频谱集中于主瓣。[南邮2009研]</span></strong></p><p class="ne-p"><span class="ne-text">A.振幅，时间</span></p><p class="ne-p"><span class="ne-text">B.频谱，波形</span></p><p class="ne-p"><span class="ne-text">C.恒定，相位</span></p><p class="ne-p"><span class="ne-text">D.波形，相位</span></p><p class="ne-p"><span class="ne-text">【答案】D</span></p><p class="ne-p"><span class="ne-text">【解析】MSK信号包络恒定、相位连续，所以频谱集中于主瓣。</span></p><p class="ne-p imgbox"><span class="image-box"><img data-original="http://image.uc.cn/s/wemedia/s/upload/2022/fd50619e1e6f57b6821022997134e89d.png" data-src="http://image.uc.cn/o/wemedia/s/upload/2022/fd50619e1e6f57b6821022997134e89d.png;,4,png;3,700x.png" src="//image.uc.cn/s/uae/g/1v/images/image-lazyload.png" uploaded="1" data-infoed="1" data-width="776" data-height="578" data-format="png" data-size="567695000" data-index="1" class="image-default-bg b-lazy" heavypress="http://image.uc.cn/o/wemedia/s/upload/2022/fd50619e1e6f57b6821022997134e89d.png;,4,png;3,700x.png" style="width: 700px !important; height: 521.392px !important;"><span class="share-import-title"></span></span></p><p class="imgbox_desc"><span>樊昌信通信原理考研真题题库视频网课！</span></p><p class="ne-p"><strong><span class="ne-text">MSK信号与PSK信号相比较其优势在于（），特别适合移动通信。[南邮2010研]</span></strong></p><p class="ne-p"><span class="ne-text">A.误码小</span></p><p class="ne-p"><span class="ne-text">B.频谱集中于主瓣</span></p><p class="ne-p"><span class="ne-text">C.容易实现调制解</span></p><p class="ne-p"><span class="ne-text">D.含离散谱</span></p><p class="ne-p"><span class="ne-text">【答案】B</span></p><p class="ne-p"><span class="ne-text">【解析】连续相位调制信号的功率谱旁瓣衰减得快，频谱集中于主瓣。</span></p><p class="ne-p"><strong><span class="ne-text">通常的模拟信号数字化包含的三步依次为（）、（）和（）。[南邮2010</span></strong></p><p class="ne-p"><span class="ne-text">A.抽样，编码，量化</span></p><p class="ne-p"><span class="ne-text">B.量化，抽样，编码</span></p><p class="ne-p"><span class="ne-text">C.抽样，量化，编码</span></p><p class="ne-p"><span class="ne-text">D.量化，编码，抽样</span></p><p class="ne-p"><span class="ne-text">【答案】C</span></p><p class="ne-p"><span class="ne-text">【解析】模拟信号经抽样变为离散模拟信号，再经量化、编码变为数字信号。</span></p><p class="ne-p"><strong><span class="ne-text">模拟信号数字化中的三种常见抽样方式是：（）抽样、（）抽样和（）抽样。[南邮2009研]</span></strong></p><p class="ne-p"><span class="ne-text">A.理想，平顶，自然</span></p><p class="ne-p"><span class="ne-text">B.理想，冲激，平顶</span></p><p class="ne-p"><span class="ne-text">C.自然，曲顶，瞬时</span></p><p class="ne-p"><span class="ne-text">D.自然，曲顶，冲激</span></p><p class="ne-p"><span class="ne-text">【答案】A</span></p><p class="ne-p"><span class="ne-text">【解析】抽样定理中要求抽样脉冲序列是理想冲激脉冲序列，称为理想抽样；实际抽样电路中的抽样脉冲具有一定的持续时间，在脉宽期间其幅度可以是不变的，称为平顶抽样；脉宽期间其幅度也可以随信号幅度而变化，称为自然抽样。</span></p><p class="ne-p"><span class="ne-text">........</span></p><p class="ne-p"><strong><span class="ne-text">>>>本文为节选>>>相关资料均载于攻关学习网>>>每年更新！</span></strong></p><br>最后别忘了到沪学网下载免费课程！
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