ANALOG OPTICAL FIBER LINK

摘要

PURPOSE:To automatically reduce the occurrence of interference noise based on the variance of the luminescence wavelength due to the temperature variance or the secular change with respect to wavelength multiplex transmission. CONSTITUTION:Signals from terminals 131 to 13n are subjected to wavelength multiplexing and are transmitted by an optical fiber 12 and are collectively converted to an RF signal by a photoelectric transducer 19. The noise level on the outside of the RF signal band is measured by a wavelength control circuit 21 and is compared with the just preceding noise level, and a wavelength control signal is so generated that the noise is reduced, and a terminal is designated, and it is supplied to an electrooptical transducer 18 as the RF signal on the outside of the transmission RF band. The wavelength control signal is extracted from the converted electric signal by a reception circuit 19 in the designated terminal, and the driving current of a laser diode 17 is controlled by a control circuit 31.