Method for controlling performance of optical amplifiers

A method for controlling gain of an optical amplifier, said method including the following steps:

• (i) obtaining digital value for input and output power electronic circuitry DC offset;
• (ii) if control mode is gain control, then selecting the following set point values:
• power set point=0.0, gain set point=desired gain;
• (iii) obtaining digital value representing signal input value and subtracting the input power electronic circuitry DC offset to produce adjusted input power value;
• (iv) obtaining value representing signal output value and subtracting the output power electronic circuitry DC offset to produce adjusted output power value;
• (v) multiplying the gain setpoint by said obtained adjusted input power value and subtracting from this product the adjusted output power value to produce gain control error signal;
• (vi) subtracting said gain control error signal from any number to produce a controller input signal;
• (vii) transforming by a control algorithm said controller input signal into digital representation of at least one pump control signal;
• (viii) transforming said digital representation of said at least one pump control signal into at least one corresponding analog pump control signal;
• and
• (ix) applying said at least one analog pump control signal to at least one pump via pump driver circuitry.

A method for controlling gain of an optical amplifier, said method including the following steps:

• (i) obtaining value for input and output power electronic circuitry DC offset;
• (ii) if control mode is gain control, then selecting the following set point values:
• power set point=0.0, gain setpoint=desired gain;
• (iii) obtaining digital value representing signal input value and subtracting the output power electronic circuitry DC offset to produce adjusted input power value;
• (iv) obtaining digital value representing signal output value and subtracting the output power electronic circuitry DC offset to produce adjusted output power value;
• (v) dividing said adjusted output power value by gain set point and subtracting from this adjusted input power to obtain gain control error signal;
• (vi) subtracting said gain control error signal from any number to produce a controller input signal;
• (vii) transforming said controller input signal into digital representation of at least one pump control signal by a control algorithm;
• (viii) transforming said digital representation of said at least one pump control signal into at least one corresponding analog pump control signal;
• and
• (ix) applying said at least one analog pump control signal to at least one pump via pump driver circuitry.

A method for controlling gain of an optical amplifier, said method including the following steps:

• (i) obtaining value for input and output power electronic circuitry DC offset;
• (ii) specifying a desired control mode among at least two control modes, said two control modes being Gain control and output power control;
• (iii) if control mode is gain control then selecting the following set point values:
• power set point=0.0, gain set point=desired gain;
• (iv) obtaining digital value representing signal input value and subtracting the input power electronic circuitry DC offset to produce adjusted input power value;
• (v) obtaining digital value representing signal output value and subtracting the output power electronic circuitry DC offset to produce adjusted output power value;
• (vi) either multiplying the gain setpoint by said obtained adjusted input power value and subtracting this from the adjusted output power value, or dividing said adjusted output power value by gain set point and subtracting from this adjusted input power to obtain gain control error signal;
• (vii) subtracting said gain control error signal from any number to produce a controller input signal;
• (viii) transforming said controller input signal into digital representation of at least one pump control signal by a control algorithm;
• (ix) transforming said digital representation of said at least one pump control signal into at least one corresponding analog pump control signal;
• and
• (x) applying said at least one analog pump control signal to at least one pump via pump driver circuitry.

A method for controlling output power of an amplifier, said method including the following steps:

• (i) obtaining value for output power electronic circuitry DC offset;
• (ii) specifying a desired control mode among at least two control modes, wherein one of said two control modes being output power control;
• (iii) if control mode is output power control, then selecting the following set pint values:
• output power set point=desired power, gain setpoint=0.0;
• (iv) obtaining digital value representing signal output value and subtracting output power electronic circuitry DC offset to produce adjusted output power value;
• (v) subtracting said adjusted output power from output power set-point, producing a controller input signal;
• (vi) transforming said controller input signal into digital representation of at least one pump control signal by a control algorithm;
• (vii) transforming said digital representation of said at least one pump control signal;
• and
• (viii) applying said at least one analog pump control signal to at least one pump via pump driver circuitry.

A method for controlling pump current optical power, including the following steps:

• (i) obtaining value for current that is fed to the pump and electronic circuitry DC offset;
• (ii) specifying a desired control mode among at least two control modes, wherein one of said two control modes being pump current control;
• (iii) if control mode is pump current control, then selecting the following set point values:
• pump current set point=desired pump current, pump power set point=0.0;
• (iv) obtaining digital value representing pump current value and subtracting the electronic circuitry DC offset to produce adjusted pump current value;
• (v) subtracting said adjusted pump current value from pump current set-point, producing a controller input signal;
• (vii) transforming said controller input signal into digital representation of at least one pump control signal by a control algorithm;
• (viii) transforming said digital representation of at least one pump control signal into at least one corresponding analog pump control signal;
• and
• (ix) applying said at least one analog pump control signal to at least one pump via driver circuitry.

A method for controlling pump optical power, including the following steps:

• (i) obtaining value for optical pump power and electronic circuitry DC offset;
• (ii) specifying a desired control mode among at least two control modes, wherein one of said two control modes being optical pump power control;
• (iii) if control mode is optical pump power control, then selecting the following set point values:
• pump current set point=0.0, optical pump power set point=desired value;
• (iv) obtaining a digital value representing optical pump power value and subtracting electronic circuitry DC offset to produce adjusted optical pump power value;
• (v) subtracting said adjusted optical pump power value from pump optical pump power set point, producing a controller input signal;
• (vi) transforming said controller input signal into digital representation of at least one pump control signal by a control algorithm;
• (vii) transforming said digital representation of said at least one pump control signal into at least one corresponding analog pump control signal;
• and
• (viii) applying said at least one analog pump control signal to at least one pump via driver circuitry.

A method for compensating for ASE in gain control mode while controlling gain of an optical amplifier, said method including the following steps:

• (i) obtaining value for input and output power electronic circuitry DC offset;
• (ii) selecting the following set point values:
• power set point=0.0, gain set point=desired gain,
• (iii) obtaining digital value representing signal input value and subtracting input power electronic circuitry DC offset to produce adjusted input power value;
• (iv) obtaining digital value representing signal output value and subtracting output power electronic circuitry DC offset to produce adjusted output power value;
• (v) obtaining the ASE content of said adjusted input power value by either utilizing a lookup table or a formula and subtract ASE content from said adjusted input power value to produce ASE adjusted output power value;
• (vi) either multiplying the gain setpoint by said obtained ASE adjusted input power value and subtracting this from the ASE adjusted output power value, or dividing said ASE adjusted input power to obtain gain control error signal;
• (vii) subtracting said gain control error signal from any number to produce a controller input signal;
• (viii) transforming said controller input signal into digital representation of at least one pump control signal by a control algorithm;
• (xi) transforming said digital representation of said at least one pump control signal into at least one corresponding analog pump control signal;
• and
• (x) applying said at least one analog pump control signal to at least one pump via driver circuitry.

A method for compensating for ASE in output power control mode of amplifier, said method including the following steps:

• (i) obtaining value for output power electronic circuitry DC offset;
• (ii) specifying a desired control modes being output power control;
• (iii) if control mode is output power control then selecting the following set point values:
• output power set point=desired power, gain set point=0.0,
• (iv) obtaining digital value representing signal output value and subtracting output electronic circuitry DC offset to produce adjusted output power value;
• (v) utilizing a lookup table or formula to obtain the ASE adjusted output power from output power value;
• (vi) subtracting said ASE adjusted output power from output power set point, producing a controller input signal;
• (vii) transforming said controller input signal into digital representation of at least one pump control signal by a control algorithm;
• (viii) transforming said digital representation of said at least one pump control signal into at least one corresponding analog pump control signal;
• and
• (ix) applying said at least one analog pump control signal to at least one pump via pump driver circuitry.