Analysis For Active Spontaneous Emission In EDFA Pumped By Pulse

Erbium-doped fiber amplifier has established its status in the field of optical communication because of its unique advantages; and it is also very important to the development of all-optical communication. The active spontaneous emission noise plays an important role in erbium-doped fiber amplifier; what’s more, as the source to start-up the erbium-doped fiber laser, it also seriously influences the performance of erbium-doped fiber laser. So the research of active spontaneous emission of erbium-doped fiber has never stopped. However, all the researches before were carried out under continuous light pump. Compared to continuous light pump, the pulse light pump has many advantages such as low energy consumption, low noise and waveform-shaped. So studying active spontaneous emission under pulse-pump has important academic significance.Begun the research with rate equation, this paper has broken the limitation of pump waveform to study the active spontaneous emission of erbium-doped fiber pumped by arbitrary waveform pulse. By dividing the time into tiny periods, we obtained the expression for population distribution of each level and average power of the active spontaneous emission. And then we have simulated situations pumped by the ideal rectangular pulse and two other non-ideal waveform pulse respectively. The experiments show that the results consistent with the theoretical analysis. These researches can be used to all-optical modulation for the optical fiber laser.