Hybrid random fiber laser distributed amplification method based on erbium fiber with low doping concentration

A hybrid distributed amplification method based on random lasing generated within weak erbium-doped fiber (WEDF), comprises steps of:

• step (1) constructing a fiber link via WEDF;
• step (2) combined with the pump source, the wavelength division multiplexer and the strong feedback module, generating a random fiber laser based on the fiber link;
• step (3) constructing a pump for amplification of WEDF based on the random fiber laser, meanwhile performing distributed Raman amplification by the random fiber laser, so that a distributed amplification method using the hybrid of WEDF and Raman effects is capable of constructing a spatially equalized gain distribution along the fiber;
• and
• step (4) performing hybrid distributed amplification within WEDF and the Raman fiber random laser to achieve spatially equalized gain distribution along the fiber.