Disclosed are fiber amplifiers with multiple pumping sources including multiple optical sources or an optical comb source with multiple spectral lines. A comb source may include generating a plurality of evenly spaced or nearly evenly spaced spectral lines. The optical comb source may pump a fiber by propagating optical energy at the multiple spectral lines through the fiber. The comb source may cause gain in the fiber at in a band of wavelengths different from the spectral lines of the comb source. A weak signal injected into the fiber that propagates in the fiber will experience optical gain in the fiber producing an amplified signal at the wavelength within a band of wavelengths different from the comb source wavelengths. When the bandwidth of the multiple bands of gain is wide, the amplifier may be referred to as an ultra-wideband amplifier.

An intelligence-defind optical tunnel network system includes a first tier network and a second tier network. The first tier network includes multiple pods, any one of which includes multiple Optical Add-Drop Sub-systems (OADS) configured to transmit data between corresponding servers through ToR switches. The second tier network includes multiple Optical Switch Interconnect Sub-systems (OSIS). Any two of the OSISs transmit a corresponding lateral optical signal via a first line correspondingly. Any two adjacent OSISs are coupled to the OADSs in the same pod of the first tier via multiple optical paths respectively.

An intelligence-defind optical tunnel network system includes a first tier network and a second tier network. The first tier network includes multiple pods, any one of which includes multiple Optical Add-Drop Sub-systems (OADS) configured to transmit data between corresponding servers through ToR switches. The second tier network includes multiple Optical Switch Interconnect Sub-systems (OSIS). Any two of the OSISs transmit a corresponding lateral optical signal via a first line correspondingly. Any two adjacent OSISs are coupled to the OADSs in the same pod of the first tier via multiple optical paths respectively.

An object is to provide an optical amplifier capable of performing Raman amplification while suppressing power consumption and a size. A multicore fiber has a double clad structure. The double clad structure includes a plurality of cores thorough which an optical signal is transmitted and a clad includes the cores. A light source outputs a pump light used for amplifying the optical signal by stimulated Raman scattering in the multicore fiber. The pump light is generated by multiplexing multimode laser lights. A optical coupler couples the pump light into the clad of the multicore fiber.

Disclosed is a submarine network device, comprising a fiber set, a pump laser set, an erbium doped fiber amplifier (EDFA) set, a primary fiber coupler (CPL) set and a secondary CPL set, wherein the primary CPL set comprises N primary CPLs, the secondary CPL set comprises N secondary CPLs, with N being an integer greater than or equal to 3. The fiber set is configured to connect the pump laser set, the primary CPL set, the secondary CPL set and the EDFA set. An input port of each primary CPL in the primary CPL set is at least connected with a pump laser. An output port of each secondary CPL in the secondary CPL set is at least connected with an EDFA. Output ports of each primary CPL in the primary CPL set are respectively connected with two different secondary CPLs that are spaced by a secondary CPL, and input ports of each secondary CPL in the secondary CPL set are respectively connected with two different primary CPLs that are spaced by a primary CPL.

Disclosed is a submarine network device, comprising a fiber set, a pump laser set, an erbium doped fiber amplifier (EDFA) set, a primary fiber coupler (CPL) set and a secondary CPL set, wherein the primary CPL set comprises N primary CPLs, the secondary CPL set comprises N secondary CPLs, with N being an integer greater than or equal to 3. The fiber set is configured to connect the pump laser set, the primary CPL set, the secondary CPL set and the EDFA set. An input port of each primary CPL in the primary CPL set is at least connected with a pump laser. An output port of each secondary CPL in the secondary CPL set is at least connected with an EDFA. Output ports of each primary CPL in the primary CPL set are respectively connected with two different secondary CPLs that are spaced by a secondary CPL, and input ports of each secondary CPL in the secondary CPL set are respectively connected with two different primary CPLs that are spaced by a primary CPL.

An optical communication system includes an optical transmitter and one or more processors. The optical transmitter is configured to output an optical signal, and includes an average-power-limited optical amplifier, such as an erbium-doped fiber amplifier (EDFA). The one or more processors are configured to receive optical signal data related to a received power for a communication link from a remote communication system and determine that the optical signal data is likely to fall below a minimum received power within a time interval. In response to the determination, the one or more processors are configured to determine a duty cycle of the optical transmitter based on a minimum on-cycle length and a predicted EDFA output power and operate the optical transmitter using the determined duty cycle to transmit an on-cycle power that is no less than the minimum required receiver power for error-free operation of the communication link.

An optical communication system includes an optical transmitter and one or more processors. The optical transmitter is configured to output an optical signal, and includes an average-power-limited optical amplifier, such as an erbium-doped fiber amplifier (EDFA). The one or more processors are configured to receive optical signal data related to a received power for a communication link from a remote communication system and determine that the optical signal data is likely to fall below a minimum received power within a time interval. In response to the determination, the one or more processors are configured to determine a duty cycle of the optical transmitter based on a minimum on-cycle length and a predicted EDFA output power and operate the optical transmitter using the determined duty cycle to transmit an on-cycle power that is no less than the minimum required receiver power for error-free operation of the communication link.

Disclosed are techniques and amplifier stages that include wave division multiplexers, semiconductor optical amplifiers and wave division demultiplexers that amplify optical signals. An input optical signal having a first bandwidth is partitioned into a plurality of subband optical signals by thin film filters tuned to a selected bandwidth that is less than the first bandwidth. Each of the plurality of subband optical signals has a bandwidth that is a portion of the first bandwidth. Each subband optical signal is input into a semiconductor optical amplifier that is tuned to the respective portion of the first bandwidth that corresponds to the subband optical signal. The combination of the partitioned input optical signal and tuned semiconductor optical amplifiers provides improved optical signal transmission performance by reducing polarization dependent gain.

Described herein are photonic integrated circuits (PICs) comprising a semiconductor optical amplifier (SOA) to output a signal comprising a plurality of wavelengths, a sensor to detect data associated with a power value of each wavelength of the output signal of the SOA, a filter to filter power values of one or more of the wavelengths of the output signal of the SOA, and control circuitry to control the filter to reduce a difference between a pre-determined power value of each filtered wavelength of the output signal of the SOA and the detected power value of each filtered wavelength of the output signal of the SOA.