试题详情

试题内容

Although a given waveform may contain frequencies over a very broad range, as a practical matter any transmission system will be able to accommodate only a limited band of  (1)  . This, in turn, limits the data rate that can be carried on the transmission  (2)  . A square wave has an infinite number of frequency components and hence an infinite  (3)  .However, the peak amplitude of the kth frequency component, kf, is only 1/k, so most of the    (4)  in this waveform is in the first few frequency components. In general, any digital waveform will have  (5)  bandwidth. If we attempt to transmit this waveform as a signal over any medium, the transmission system will limit the bandwidth that can be transmitted.
(1)A、frequencies
B、connections
C、diagrams
D、resources
(2)A、procedures
B、function
C、route
D、medium
(3)A、source
B、bandwidth
C、energy
D、cost
(4)A、frequency
B、energy
C、amplitude
D、phase
(5)A、small
B、limited
C、infinite
D、finite

查看答案

软题库参考答案:A、D、B、B、C(仅供参考)

软题库解析:正在加载....

你可能感兴趣的试题

35题:在接收邮件时,客户端代理软件与POP3服务器通过建立( )连接来传送报文。
A.UDP
B.TCP
C.P2P
D.DHCP
28题:SMTP的默认服务端口号是( )。
A.25
B.80
C.110
D.143
54题:

可以采用静态或动态方式来划分VLAN,下面属于静态划分的方法是 ( ) 。
A、按端口划分
B、按MAC地址划分
C、按协议类型划分
D、按逻辑地址划分

18题:

边界网关协议BGP4是一种动态路由发现协议,它的主要功能是(1) 。BGP路由器之间传送的是AS路径信息,这样就解决了(2) 问题。BGP4报文封装在 (3)。
(1)A.发现新的路由
B.计算最短通路
C.控制路由策略
D.维护网络拓扑数据库
(2)A.路由环路
B.最短通路
C.路由计算
D.路由更新
(3)A.IP数据报
B.以太帧
C. TCP报文
D.UDP报文

71题:

The TCP protocolis a (1) layer protocol. Each connection connects two TCPs that may be just one physical network apart or located on opposite sides ofthe globe. In other words, each connection creates a (2) witha length that may be totally different from another path created by another connection. This means that TCP cannot use the same retransmission time for all connections. Selecting afixed retransnussion time for all connections can result in serious consequences. Ifthe retransmission ti7题:

软件风险一般包含  ( )  两个特性。
A、救火和危机管理
B、已知风险和未知风险
C、不确定性和损失
D、员工和预算