| 摘要 |
Multichannel wavelength monitoring apparatus comprises inputs (33) for receiving multichannel optical signals, toning VOA banks (34) for applying respective identifying signals of different frequencies f1, f2, f3 and f4 to the multichannel signals, an OCM (32) for demultiplexing the multichannel signals, and a photodiode array (36) for detecting the optical output signals from OCM (32) produced by such and for producing an electrical output signal. A DSP (35) differentiates, on the basis of the identifying signals detected by the array (36), the components of the electrical output signal derived from the different multichannel signals. The four inputs (33) of the OCM (32) are spaced at a quarter (or one and a quarter times) the channel spacing in order to ensure that the output signals are correctly positioned to be detected by the photodiodes. The DSP (35) passes data to the outputs (37) indicative of parameters of the channels of each input signal, such as the relative power/amplitude of each channel, the wavelength of each channel and the optical signal-to-noise ratio.
|
