| 摘要 |
PURPOSE:To extend the transmission distance and to improve the reliability by using one repeater so as to relay an optical pulse signal and demodulate the signal into a base band signal. CONSTITUTION:A PFWM multiplex signal modulated by a component video signals Y, PB, PR is employed for an inputted optical pulse signal. The optical pulse signal is converted into an electric signal by a light receiving element 10, amplified by a light receiving circuit 11 and the pulse signal is recovered by an identification recovery circuit 12. The recovered pulse signal is converted directly into the optical pulse signal by a drive circuit 15 and a light emitting element 16 and the result is outputted. On the other hand, the reproduced pulse signal is inputted to a demodulation circuit 13, in which original base band signals Y, PB, PR are demodulated. Thus, one optical repeater attains the relay of a pulse converted analog signal and viewing of an original video or audio signal simultaneously. Thus, the transmission distance is extended, and the reliability of the video audio distribution system and ease of maintenance are improved. |
