Wavelength division multiplexing optical transmission system and wavelength division multiplexing optical transmission method

A wavelength division multiplexing optical transmission system comprising:

• an optical transmitter for transmitting, to an optical fiber transmission path, a WDM signal which is obtained by multiplexing a plurality of optical signals on the optical fiber transmission path in terms of wavelength, the plurality of optical signals respectively having negative chirps, and the plurality of optical signals differing from one another in wavelength;
• an optical receiver for receiving the WDM signal from the optical fiber transmission path;
• and
• at least one relay node which is provided between the optical transmitter and the optical receiver,
• wherein each of the relay node and the optical receiver includes a dispersion compensator for compensating a chromatic dispersion suffered in the optical fiber in the immediately preceding transmission span, and
• wherein at least one of the relay nodes further includes a dispersion adder for adding a predetermined positive dispersion amount to the WDM signal before the WDM signal is transmitted to the optical fiber in the following transmission span.

A wavelength division multiplexing optical transmission system comprising:

• optical transmission means for transmitting, to an optical fiber transmission path, a WDM signal which is obtained by multiplexing a plurality of optical signals on the optical fiber transmission path in terms of wavelength, the plurality of optical signals respectively having negative chirps, and the plurality of optical signals differing from one another in wavelength;
• optical reception means for receiving the WDM signal from the optical fiber transmission path;
• and
• at least one relay node means which is provided between the optical transmission means and the optical reception means,
• wherein the optical transmission means includes dispersion adding means for beforehand adding a predetermined positive dispersion amount to the WDM signal before the WDM signal is transmitted, and
• wherein each of the relay node means and the optical reception means includes dispersion compensating means for compensating a chromatic dispersion suffered in the optical fiber in the immediately preceding transmission span.

A wavelength division multiplexing optical transmission system comprising:

• optical transmission means for transmitting, to an optical fiber transmission path, a WDM signal which is obtained by multiplexing a plurality of optical signals on the optical fiber transmission path in terms of wavelength, the plurality of optical signals respectively having negative chirps, and the plurality of optical signals differing from one another in wavelength;
• optical reception means for receiving the WDM signal from the optical fiber transmission path;
• and
• at least one relay node means which is provided between the optical transmission means and the optical reception means,
• wherein each of the relay node means and the optical reception means includes dispersion compensating means for compensating a chromatic dispersion suffered in the optical fiber in the immediately preceding transmission span, and
• wherein at least one of the relay node means further includes dispersion adding means for adding a predetermined positive dispersion amount to the WDM signal before the WDM signal is transmitted to the optical fiber in the following transmission span.

A wavelength division multiplexing optical transmission method in a wavelength division multiplexing optical transmission system including an optical transmitter, an optical receiver and at least one relay node which is provided between the optical transmitter and the optical receiver, the transmission method comprising the steps of:

• causing the optical transmitter to add a predetermined positive dispersion amount to a WDM signal which is obtained by multiplexing a plurality of optical signals on the optical fiber transmission path in terms of wavelength, and to thus transmit the WDM signal to an optical fiber transmission path, the plurality of optical signals modulated by an optical modulator so as to respectively have negative chirps, and the plurality of optical signals differing from one another in wavelength;
• causing each of the relay nodes to compensate a chromatic dispersion, which the received WDM signal has suffered in the optical fiber in the immediately preceding transmission span, and to thus transmit the WDM signal to the transmission path in the following transmission span;
• and
• causing the optical receiver to compensate a chromatic dispersion, which the received WDM signal has suffered in the optical fiber in the immediately preceding transmission span, and to thereby obtain the received WDM signal, which includes the predetermined positive dispersion amount.

A wavelength division multiplexing optical transmission method in a wavelength division multiplexing optical transmission system including an optical transmitter, an optical receiver and at least one relay node which is provided between the optical transmitter and the optical receiver, the transmission method comprising the steps of:

• causing the optical transmitter to transmit, to an optical fiber transmission path, a WDM signal which is obtained by multiplexing a plurality of optical signals on the optical fiber transmission path in terms of wavelength, the plurality of optical signals respectively having negative chirps, and the plurality of optical signals differing from one another in wavelength;
• causing each of the relay nodes to compensate a chromatic dispersion, which the received WDM signal has suffered in the optical fiber in the immediately preceding transmission span, and to thus transmit the WDM signal to the transmission path in the following transmission span;
• causing at least one of the relay nodes to further add a predetermined positive dispersion amount to the WDM signal before the WDM signal is transmitted to the optical fiber in the following transmission span;
• and
• causing the optical receiver to compensate a chromatic dispersion, which the received WDM signal has suffered in the optical fiber in the immediately preceding transmission span, and to thereby obtain the received WDM signal, which includes the predetermined positive dispersion amount.