Apparatus and method for amplification medium performance simulation, and optical amplifier

The amplification medium performance simulation apparatus according to claim 1, wherein said simulation executing unit comprises:na population inversion rate calculating unit for calculating a population inversion rate on the basis of a signal light power according to a position with a coordinate in the longitudinal direction of said amplification medium;a population inversion rate change quantity calculating unit for calculating a quantity of a change in population inversion rate which may occur due to a fluctuation in ion population at the metastable energy level of said amplification medium caused by input of said input signal light, as a function of a wavelength of the input signal light and a position in the longitudinal direction of said amplification medium, by using the population inversion rate calculated by said population inversion rate calculating unit and contents retained in said basic data retaining unit and said input signal light information retaining unit;a signal light power change calculating unit for performing calculation of a change in optical power of the signal light propagating through said amplification medium from a signal light input end in said amplification medium in each of minute propagation ranges started from the signal light input end and terminated at a signal light output end, by using a differential equation defined by the quantity of a change in population inversion rate calculated by said population inversion rate change quantity calculating unit and the contents retained in said basic data retaining unit and said input signal light information retaining unit;a signal light power calculating unit for adding, in order, changes in optical power in the minute propagation ranges from a change in optical power in the minute range at the signal input end as a starting point to a change in optical power in the minute range at the signal light output end as a terminating point calculated by said signal light power change calculating unit to the power value of the input signal light retained in said input signal light information retaining unit between the signal light input end and the signal light output end, to calculate a signal light power according to a position with a coordinate in the longitudinal direction of the signal light propagating in said amplification medium including the fluctuation in ion population at the metastable energy level in said amplification medium caused by input of said input signal light; andan outputting process unit for outputting a result of calculation of the power of the signal light outputted from the signal light output end calculated by said signal light power calculating unit as a result of simulation of the performance of said amplification medium.

The optical amplifier according to claim 12, wherein said pumping source controlling unit comprises:na first power monitor for monitoring powers of the input signal light and the output signal light;a wavelength allocation information obtaining unit for obtaining wavelength allocation information on a signal light propagating in said amplification medium;an automatic gain control unit for outputting a signal for controlling said pumping source obtained on the basis of the powers of the input signal light and the output signal light monitored by said first power monitor so that a gain of said optical signal amplification medium is constant; anda correcting unit for correcting a control quantity for said pumping source in said automatic gain control unit on the basis of the wavelength allocation information obtained by said wavelength allocation information obtaining unit so that gain deviation in a wavelength band due to spectral hole burning decreases.

The optical amplifier according to claim 12, said pumping source controlling unit comprises:na second power monitor for obtaining powers of the input signal light and the output signal light in each of a plurality of bands divided on the basis of a result of the simulation obtained by said amplification medium performance simulation apparatus; andan automatic average gain control unit for outputting a signal for controlling said pumping source on the basis of the powers of the input signal light and the output signal light in each of the bands obtained by said second power monitor so that average gains in said bands are equalized.

The optical amplifier according to claim 12, wherein said simulation executing unit comprises:na population inversion rate calculating unit for calculating a population inversion rate on the basis of a signal light power according to a position with a coordinate in the longitudinal direction of said amplification medium;a population inversion rate change quantity calculating unit for calculating a quantity of a change in population inversion rate which may occur due to a fluctuation in ion population at the metastable energy level of said amplification medium caused by input of said input signal light, as a function of a wavelength of the input signal light and a position in the longitudinal direction of said amplification medium, by using the population inversion rate calculated by said population inversion rate calculating unit and contents retained in said basic data retaining unit and said input signal light information retaining unit;a signal light power change calculating unit for performing calculation of a change in optical power of the signal light propagating through said amplification medium from a signal light input end in said amplification medium in each of minute propagation ranges started from the signal light input end and terminated at a signal light output end, by using a differential equation defined by the quantity of a change in population inversion rate calculated by said population inversion rate change quantity calculating unit and the contents retained in said basic data retaining unit and said input signal light information retaining unit;a signal light power calculating unit for adding, in order, changes in optical power in the minute propagation ranges from a change in optical power in the minute range at the signal input end as a starting point to a change in optical power in the minute range at the signal light output end as a terminating point calculated by said signal light power change calculating unit to the power value of the input signal light retained in said input signal light information retaining unit between the signal light input end and the signal light output end, to calculate a signal light power according to a position with a coordinate in the longitudinal direction of the signal light propagating in said amplification medium including the fluctuation in ion population at the metastable energy level in said amplification medium caused by input of said input signal light; andan outputting process unit for outputting a result of calculation of the power of the signal light outputted from the signal light output end calculated by said signal light power calculating unit as a result of simulation of the performance of said amplification medium.

The optical amplifier according to claim 12, wherein said population inversion rate change quantity calculating unit uses at least one or more Gaussian functions as functions for calculating the quantity of a change in the population inversion rate.