| 摘要 |
PURPOSE:To simplify the circuit, to reduce power comsumption, to increase signal detecting sensitivity and to extend the transmission range by outputting optical signals opposite in polarity to each other from two light emitting elements, and receiving them by two photodetectors and combining electrically said two signals. CONSTITUTION:A ternary data signal applied to an input terminal is a digital signal having -1, 0, +1 of ternary logical levels and converted into two rows of binary signals by a ternary/binary converting circuit 1. The two rows of binary data signals are both logical 0 when the original signals are logical 0, and one is logical 1 and the other is logical 0 when they are logical +1 or -1. When they are +1, -1, however, a channel outputting 1 is replaced and made opposite to each other. The two rows of the binary data signals are converted into optical signals at light emitting elements 4, 5 via amplifier circuits 2, 3 and transmitted to optical fibers 6, 7. The two rows of the binary data signals reproduced by photodetectors 8, 9 at the receiving section are added at receiving amplifier circuits 10, 11 where the direction of ''1'' of the two rows of the binary data signals is set so as to be opposite to each other and a ternary signal is obtained. |
