Patent ID: 6295147
Filing Date: 2001-09-25
Classification: H04B,H04J

Abstract:
A wavelength multiplexing transmission apparatus comprising:a plurality of optical signal outputting sections for outputting optical signals having different wavelengths from each other; anda wavelength multiplexing section, connected to said plurality of optical signal outputting sections, for multiplexing the optical signals outputted from said plurality of optical signal outputting sections and transmitting the multiplexed optical signal;wherein each of said optical signal outputting sections includes:a transmission light source driven by an electric signal for outputting an optical signal of a predetermined wavelength,a wavelength filter, connected to said transmission light source, for receiving the optical signal and allowing an optical signal with the predetermined wavelength to pass through and outputting the optical signal with the wavelength to prevent a crosstalk caused by a wavelength drift of the optical signal outputted from said transmission light source,a first abnormal condition detecting section, connected to said wavelength filter, for detecting an abnormal condition of an output level of the optical signal passed through said wavelength filter by monitoring whether a level of the optical signal passed through said wavelength filter is lower than a first threshold level set in advance, anda second abnormal condition detecting section, connected to said transmission light source, for detecting an abnormal condition of an output level of the optical signal outputted from said transmission light source, anda third abnormal condition detecting section, connected both to said first abnormal condition detection section and said second abnormal condition detection section, for detecting an abnormal condition of a wavelength of the optical signal outputted from said transmission light source when an abnormal condition is detected by said first abnormal condition detecting section and a normal condition is detected by said second abnormal condition detecting section.