| 摘要 |
<p>When a transmitting-end device connected to a network system outputs a bi-phase shift keyed digital signal, a digital signal detecting circuit at a receiving end is complicated. Then, an interface apparatus (4) intervening between the transmitting-end device and a communication path (6) converts the bi-phase shift keyed transmitted data (S) into an amplitude shift keyed transmission signal, and outputs this transmission signal to the communication path (6). In the interface apparatus (4), a modulation scheme converting circuit (12) converts the transmitted data (S) into an NRZ modulated digital signal, and an amplitude modulating circuit (14) modulates, in accordance with the NRZ signal, the amplitude of the carrier to produce the transmission signal. In an interface apparatus (4) at the receiving end, a detecting circuit (22) detects the transmission signal to extract the NRZ modulated digital signal therefrom. A modulation scheme reverse converting circuit (24) converts the NRZ signal into the bi-phase signal, and then outputs the bi-phase signal to the receiving-end device.</p> |
