| 摘要 |
PURPOSE:To set the wavelength of each local oscillation light so that the appropriate correspondence is secured between channels at the transmitter and receiver sides, by attaining the identification of each channel. CONSTITUTION:The channel identifying signal 5 is inserted every bit after a frame cycle pulse 9 within a single frame and the same code is repeated every 10 frames. The code strings of the signal 5 are formed in different constitutions for each channel. The 1st channel signal light 7 undergoes the wavelength multiplexing with the 2nd-10th channel signal light 52-60 through a multiplexing circuit 10 and travels into an optical fiber transmission line 40. The multiplexed light 11 passed through the line 40 is divided equally by an optical distributor 12 and sent to the 1st-10th channel reception parts in the form of the 1st-10th distribution light 71-80 respectively. A channel identifying circuit 21 performs its function by reading out the pulse 9 at first and then the pulses following the pulse 9 by a step successively through gates. Then the channel numbers are detected out of the code strings. |
