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This modulated carrier is then transmitted to the required destination where it is received and the original information signal is obtained by modulation.
A. 对
B. 错
Sophisticated techniques have been developed for this process by using magnetic carrier waves operating at radio frequencies as well as microwave and millimeter wave frequencies.
A. 对
B. 错
The information source provides an electrical signal to a transmitter comprising an electrical stage which drives an optical source to give modulation of the lightwave carrier.
A. 对
B. 错
The transmission medium consists of an optical fiber cable and the receiver.
A. 对
B. 错