设信道的码元速率为600波特，采用QPSK调制，则信道的数据速率为（）b/s。
- A.300
- B.600
- C.800
- D.1200
正确答案及解析
正确答案
解析
码元速率（波特率）：即单位时间内载波参数（相位、振幅、频率等）变化的次数，单位为波特，常用符号Baud表示，简写成B。比特率（信息传输速率、信息速率）：指单位时间内在信道上传送的数据量（即比特数），单位为比特每秒（bit/s），简记为b/s或bps。波特率与比特率有如下换算关系：数据速率=Blog2N=600*log24=1200bps。
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