问题 单项选择题

在一个带宽为3 KHz、没有噪声的信道,传输二进制信号能够达到的极限数据数率为 (14) 。一个带宽为3 KHz、信噪比为30 dB的信道,能够达到的极限数据传输率为 (15) 。上述结果表明, (16)
根据奈奎斯特第十定理,为了保证传输质量,达到3 Kb/s的数据传输率需要的带宽为 (17)
在一个无限带宽的无噪声信道上,传输二进制信号,当信号的带宽为3 KHz时,能达到的极限数据传输率为 (18) Kb/s。

A.有噪声信道比无噪声信道具有更大的带宽

B.有噪声信道与无噪声信道没有可比性

C.有噪声信道比无噪声信道可达到更高的极限数据传输率

D.上述值都为极限值,条件不同,不能进行直接的比较

答案

参考答案:D

完形填空
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小题3:
A.shallowB.importantC.respectfulD.delighted
小题4:
A.recognizedB.regrettedC.realizedD.reminded
小题5:
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小题6:
A.potentialB.abilityC.possibilityD.reputation
小题7:
A.signB.senseC.rayD.bunch
小题8:
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小题10:
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小题11:
A.satisfiedB.fortunateC.successfulD.safe
小题12:
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单项选择题