PULSIFICATION FM SIGNAL OPTICAL TRANSMISSION EQUIPMENT

摘要

PURPOSE:To perform multiplex transmission to a pulsification FM signal and a low speed signal by using the pulsizing FM signal so as to turn on/off a current flowing to a lighting source. CONSTITUTION:A video signal base band signal inputted to an input terminal 101 is converted into the pulsizing FM signal by a modulator 102 to turn on/off a switch 103. A light emitting diode 106 is driven by a switched current. On the other hand, the current flowing to the switch 103 is modulated by a transistor (TR) 105 according to a data signal inputted from a terminal 104. Then an optical signal from the light emitting diode 106 is sent through an optical fiber and photoelectric-transformed by a photodetector 107. The signal is demultiplexed into a high frequency signal and a low frequency signal by a BPF 109 and an LPF 112 and the high frequency FM signal is demodulated into a video signal by a demodulator 110. Thus, the pulsification FM signal and a low speed signal is subjected to multiplex transmission.