| 摘要 |
PURPOSE: An interoffice transmit unit in a wavelength division multiplex system is provided to increase an expansibility of a system and a network by being capable of interoffice-transmitting a channel signal demultiplexed by a wavelength division, without using an extra repeater. The interoffice transmit unit is provided to detect channel errors demultiplexed by the wavelength division, without an extra counter. CONSTITUTION: In a wavelength division multiplex system which divides optical signals according to each channel, and transmits the divided signals to each determined lower systems, an interoffice transmit unit comprises an optical receiver module(200) and an optical transmitter module. The optical receiver module(200) inputs one channel signal to transmit to a lower system requested for an interoffice transmits and converts into an electronic signal, to extract data. The optical receiver module(200) is composed of an optical detect element(202), a limiting amplifier(204), a clock and data restorer(206). The optical detect element(202) detects an input channel signal optically, to convert into the electronic signal. The limiting amplifier(204) amplifies the converted electronic signal limitedly. The clock and data restorer(206) extracts the data and the clock from an output signal from the limiting amplifier(204). The optical transmitter module is connected to an interoffice optical transmit path which is connected to the lower systems and the optical receiver module(200), and converts the extracted data into an optical signal, to transmit to the lower system. |
