Abstract

To construct highly reliable undersea optical transmission systems, the configuration with remotely pumped erbium-doped fiber amplifiers (EDFAs) has been studied. Because the pumping light sources are placed at the transmitter or the receiver, not under the sea, we can increase the repeater spacing and the reliability of the system. In this configuration, the pumping light propagates through the 10-km-long optical fiber, so the loss of the optical fiber determines the required pumping power to drive the EDFA. The usual pumping wavelength for the remotely pumped EDFA is 1480 nm. But the fiber loss is relatively lower around 1530 nm, so it is convenient if we can pump EDFAs at this wavelength to transmit the signals around 1550 nm.

© 1996 Optical Society of America