Optical amplifier systems with transient control

Optical amplifier equipment that amplifies optical signals in a fiber in a communications network, comprising:

• first and second gain stages that each have fiber and at least one pump that optically pumps the fiber at a pump power to produce optical gain for the optical signals;
• a midstage module located between the first and second gain stages, wherein the midstage module includes dispersion-compensating fiber that creates an optical delay for the optical signals passing from the first gain stage to the second gain stage;
• first and second optical monitors that measure the optical signals in the optical amplifier equipment at respective locations that are located before and after the midstage module;
• and
• a control unit that uses information on the magnitude of the optical delay and the measured optical signals in the optical amplifier equipment to control the pump power of the second stage to suppress gain transients.

Optical amplifier equipment that amplifies optical signals in a fiber in a communications network, comprising:

• first and second gain stages that each have fiber and at least one pump that optically pumps the fiber at a pump power to produce optical gain for the optical signals;
• first and second optical monitors located respectively before and after the first gain stage for measuring the optical gain of the first gain stage;
• third and fourth optical monitors located respectively before and after the second gain stage for measuring the optical gain of the second gain stage;
• and
• a control unit that uses information on the measured gains of the first and second gain stages and information on the input powers to the first and second gain stages to control the pump powers of the first and second gain stages to suppress gain transients.