| 摘要 |
PURPOSE:To transmit a telephone signal without distortion, by transmitting the telephone signal by an optical repeater and an optical transmitting line for data transmission. CONSTITUTION:In stations 50i(i=1-3), a switch section is provided newly between the optical repeater 200 and a line interface 210. After an analog voice signal is voltage/frequency-converted by voltage controlled oscillators 600, 633, the signal is synchronized with a system clock for data transmission to form a digital telephone signal and outputted to optical transmission circuits 203, 204 in the optical repeater 200. A signal transmitted from the repeater 200 of a certain station to optical transmission lines 10, 10' is received at optical receiving circuits 201, 202 in the repeater 200, and inverted into the digital telephone signal. This digital telephone signal is frequency-voltage-converted at a phase locked loop 630 and restored into the analog voice signal. |
