Optical fiber communication system employing Nd doped fiber amplifier for the 1400 nm window

摘要

In accordance with the invention, an optical fiber communication system comprises one or more Nd doped fiber amplifiers for amplified transmission in the 1400 nm window. The amplifier is designed with a combination of waveguide effects and selective absorption to reduce amplified spontaneous emission to acceptable levels. The fibre waveguide has a region (50) doped with Nd and a physically separated region (31) doped with a material such as Yb which absorbs ASE at about 1050 nm. The fibre is pumped at about 800 nm to pump the Nd-doped region which acts as an amplifier for signals in the wavelength range 1350-1450 nm.