| 摘要 |
<p>PURPOSE:To suppress noises generated in a transmission system by using optical fiber for a transmission line and by providing negative feedback through the optical fiber. CONSTITUTION:At a transmission part 1, a signal from a microphone 11 is supplied through a preamplifier 12 to an amplifier 13, whose output is converted 14 into an optical signal. The optical signal is transmitted to a reception part 2 via the optical fiber 3a of a transmission line 3 to be converted 21 into an electric signal, which is led to an output terminal 22. This electric signal, after passing through a negative feedback amplifier 23, is further converted 24 into an optical signal, which is returned to the transmission part 1 through the optical fiber 3b. This optical signal is reconverted 15 into an electric signal, which is supplied to the amplifier 13 to provide negative feedback. Thus, the optical fiber is used for the transmission line and the negative feedback is provided to suppress noises generated in the transmission system.</p> |
