| 摘要 |
PURPOSE:To execute highly reliable data transmission where noise originating from a switching operation is eliminated and a noise ratio against a signal is improved. CONSTITUTION:The output signal of a modulator 12 is converted into a microwave band by a frequency converter 13 and the output is divided into two by a hybrid 14 and respectively converted into optical signals by electric/optic converters 15 and 16 so as to be duplex-transmitted by optical fibers 17 and 18. The transmitted optical signals are returned to an intermediate frequency band by frequency converters 21 and 22 after respectively converted into electric signals by the optic/electric converters 15 and 16. Phase difference between two intermediate frequency band signals is detected by the phase detecting equipment 24 of a phase control part 23 and a phase control equipment 25 controls a phase converter 26 based on the phase difference. Thus, the phases of two intermediate frequency band output signals which are respectively outputted from the frequency converter 21 and 22 become same. |
