Multi-stage optical amplifier and broadband communication system

A multi-stage optical amplifier, comprising:

• one or more optical fibers including at least a distributed Raman amplifier fiber and a discrete Raman amplifier fiber, the one or more optical fibers configured to communicate with one or more signal sources producing a plurality of signal wavelengths λs and at least two pump sources that produce one or more pump beam wavelengths λp, wherein at least one of the one or more pump beam wavelengths λp is shorter than at least a portion of the plurality of signal wavelengths λs, and wherein at least one of the distributed Raman amplifier fiber and the discrete Raman amplifier fiber comprises an optical fiber cut-off wavelength that is shorter than at least one of the one or more pump beam wavelengths λp;
• a signal output port coupled to the one or more optical fibers;
• a first pump input port, the distributed Raman amplifier fiber being positioned between the signal input port and the first pump input port and the discrete Raman amplifier fiber being positioned between the first pump input port and signal output port;
• and
• a second pump input port coupled to the one or more optical fibers and positioned between the first pump input port and the signal output port.

A multi-stage optical amplifier, comprising:

• one or more optical fibers including at least a distributed Raman amplifier fiber and a discrete Raman amplifier fiber, at least a portion of one of the distributed Raman amplifier fiber and the discrete Raman amplifier fiber comprising a dispersion compensating fiber, the one or more optical fibers configured to communicate with one or more signal sources producing a plurality of signal wavelengths λs and at least two pump sources that produce one or more pump beam wavelengths λp;
• a signal input port coupled to the one or more optical fibers;
• a first pump input port, the distributed Raman amplifier fiber being positioned between the signal input port and the first pump input port and the discrete Raman amplifier fiber being positioned between the first pump input port and signal output port;
• and
• a second pump input port coupled to the one or more optical fibers and positioned between the first pump input port and the signal output port.

A multi-stage optical amplifier, comprising:

• one or more optical fibers including at least a distributed Raman amplifier fiber and a discrete Raman amplifier fiber, the one or more optical fibers configured to receive a plurality of signal wavelengths λs;
• a signal input port coupled to the one or more optical fibers;
• a first pump input port, the distributed Raman amplifier fiber being positioned between the signal input port and the first pump input port and the discrete Raman amplifier fiber being positioned between the first pump input port and signal output port;
• a second pump input port coupled to the one or more optical fibers and positioned between the first pump input port and the signal output port;
• and
• at least a first pump source coupled to one of the first and second pump input ports, the at least a first pump source including a plurality of pump sources comprising outputs that are combined using wavelength multiplexing and using, for at least one pump wavelength, polarization multiplexing.

A multi-stage optical amplifier system, comprising:

• a plurality of transmitters that produce a plurality of signal wavelengths λs;
• a multi-stage optical amplifier comprising:
• one or more optical fibers including at least a distributed Raman amplifier fiber and a discrete Raman amplifier fiber, the one or more optical fibers communicating with the plurality of transmitters and configured to be coupled to at least two pump sources that produce one or more pump beam wavelengths λp, the distributed Raman amplifier fiber is capable of introducing an effective optical noise figure to at least a portion of the plurality of signal wavelengths λs of less than 8 dB and less than an effective optical noise figure introduced by the discrete Raman amplifier fiber, wherein at least one of the one or more pump beam wavelengths λp is shorter than at least a portion of the plurality of signal wavelengths λs, wherein the discrete Raman amplifier fiber is capable of introducing a gain level to at least some of the plurality of wavelengths λs of at least 5 dB, and wherein at least one of the distributed Raman amplifier and the discrete Raman amplifier comprises a dispersion compensating fiber;
• a signal input port coupled to the one or more optical fibers;
• a signal output port coupled to the one or more optical fibers;
• a first pump input port, the distributed Raman amplifier fiber being positioned between the signal input port and the first pump input port and the discrete Raman amplifier fiber being positioned between the first pump input port and signal output port;
• a second pump input port coupled to the one or more optical fibers and positioned between the first pump input and the signal output port, wherein the plurality of signal wavelengths λs flow in a first direction and the one or more pump beam wavelengths λp flow in a direction counter to the first direction;
• and
• a plurality of receivers coupled to the multi-stage optical amplifier.

A multi-stage optical amplifier system, comprising:

• a plurality of transmitters that produce a plurality of signal wavelengths λs;
• a multi-stage optical amplifier comprising:
• one or more optical fibers including at least a distributed Raman amplifier fiber and a discrete Raman amplifier fiber, the one or more optical fibers communicating with the plurality of transmitters and configured to be coupled to at least two pump sources that produce one or more pump beam wavelengths λp, wherein the at least one of one or more pump beam wavelengths λp are shorter than at least a portion of the plurality of signal wavelengths λs, and wherein at least one of the distributed Raman amplifier fiber and the discrete Raman amplifier fiber comprises an optical fiber cut-off wavelength that is shorter than at least one of the one or more pump beam wavelengths λp;
• a signal output port coupled to the one or more optical fibers;
• a first pump input port, the distributed Raman amplifier fiber being positioned between the signal input port and the first pump input port and the discrete Raman amplifier fiber being positioned between the first pump input port and signal output port;
• a second pump input port coupled to the one or more optical fibers and positioned between the first pump input port and the signal output port;
• and
• a plurality of receivers coupled to the multi-stage optical amplifier.

A multi-stage optical amplifier system, comprising:

• a plurality of transmitters that produce a plurality of signal wavelengths λs;
• a multi-stage optical amplifier comprising:
• one or more optical fibers including at least a distributed Raman amplifier fiber and a discrete Raman amplifier fiber, at least a portion of one of the distributed Raman amplifier fiber and the discrete Raman amplifier fiber comprises a dispersion compensating fiber, the one or more optical fibers facilitating communication with the plurality of transmitters and configured to be coupled to at least two pump sources that produce one or more pump beam wavelengths λp;
• a signal input port coupled to the one or more optical fibers, a first pump input port, the distributed Raman amplifier fiber being positioned between the signal input port and the first pump input port and the discrete Raman amplifier fiber being positioned between the first pump input port and signal output port;
• a second pump input port coupled to the one or more optical fibers and positioned between the first pump input port and the signal output port;
• and
• a plurality of receivers coupled to the multi-stage optical amplifier.

A multi-stage optical amplifier system, comprising:

• a plurality of transmitters that produce a plurality of signal wavelengths λs;
• a multi-stage optical amplifier comprising:
• one or more optical fibers facilitating communication with the plurality of transmitters and including at least a distributed Raman amplifier fiber and a discrete Raman amplifier fiber;
• a signal input port coupled to the one or more optical fibers;
• a first pump input port, the distributed Raman amplifier fiber being positioned between the signal input port and the first pump input port and the discrete Raman amplifier fiber being positioned between the first pump input port and signal output port;
• a second pump input port coupled to the one or more optical fibers and positioned between the first pump input port and the signal output port;
• at least a first pump source coupled to one of the first and second pump input ports, the at least a first pump source including a plurality of pump sources with outputs that are combined using wavelength multiplexing and using, for at least one pump wavelength, polarization multiplexing;
• and
• a plurality of receivers coupled to the multi-stage optical amplifier.