CIRCUIT FOR MODULATING OPTICAL TIME DOMAIN REFLECTOMETER TEST SIGNAL, AND PASSIVE OPTICAL NETWORK SYSTEM AND DEVICE

摘要

Embodiments of the present invention disclose an OTDR test signal modulation circuit, including a laser diode drive, a laser diode, a current adjusting unit, and an OTDR control unit. The laser diode drive is connected to the laser diode and is configured to drive, according to an input data signal, the laser diode to transmit data light. The current adjusting unit is connected to the laser diode and the OTDR control unit and is configured to adjust a current flowing through the laser diode according to an OTDR test signal provided by the OTDR control unit, so as to modulate the OTDR test signal to the data light transmitted by the laser diode. Moreover, the embodiments of the present invention also disclose a passive optical network system and apparatus.