Abstract: Optical network systems are disclosed, including systems having transmitters with a digital signal processor comprising forward error correction circuitry that provides encoded first electrical signals based on input data; and power adjusting circuitry that receives second electrical signals indicative of the first electrical signals, the power adjusting circuitry supplying third electrical signals, wherein each of the third electrical signals is indicative of an optical power level of a corresponding to one of a plurality of optical subcarriers output from an optical transmitter.

Abstract: An example method is performed by a terrestrial control system communicatively coupled to a constellation of satellites. According to the method, instructions are transmitted to a first satellite of the constellation to transmit a plurality of first groups of optical subcarriers to a plurality of second satellites of the constellation via free-space optical communication. The first groups of optical subcarriers carry first data and each of the first groups of optical subcarriers is associated, respectively, with a different communications module of the second satellites. Further, instructions are transmitted to the second satellites to transmit a plurality of second optical subcarriers to the first satellite via free-space optical communication. The second groups of optical subcarriers carry second data and each of the second groups of optical subcarriers is associated, respectively, with a different communications module of the second satellites.

Abstract: Optical network systems are disclosed, including systems having transmitters with a digital signal processor comprising forward error correction circuitry that provides encoded first electrical signals based on input data; and power adjusting circuitry that receives second electrical signals indicative of the first electrical signals, the power adjusting circuitry supplying third electrical signals, wherein each of the third electrical signals is indicative of an optical power level of a corresponding to one of a plurality of optical subcarriers output from an optical transmitter.

Abstract: Methods and systems for determining a receive signal quality of a new subcarrier group in an optical network, including a system in which each leaf node may report a current transmission output power to a hub node when it is determined that a receive signal quality of each of a plurality of subcarrier groups is within a required signal quality margin. A new leaf node may begin transmitting a new subcarrier group at a gradually increasing transmission output power until it reaches the required receive signal quality margin. The new leaf node gradually increases the transmission output power of the new subcarrier group until the hub node determines that any of the plurality of subcarrier groups and the new subcarrier group reached a maximum transmission output power or the signal quality of one or more of the plurality of subcarrier groups and the new subcarrier group begins to degrade.

Abstract: Disclosed herein are methods and systems for optimizing signal quality in an optical network having two or more hub nodes continuously outputting optical signals to a plurality of leaf nodes. Each of the plurality of leaf nodes may receive a combined optical signal from the hub nodes and determine an optical power and a signal quality of one optical subcarrier group and send a correction signal to the hub node that sent the subcarrier group. The hub nodes may send a power optimization request comprising the optical power and signal quality of each subcarrier group to a network controller. The network controller may use the optical power and signal quality to determine a power update for an optical power of the subcarrier group(s) and send the power update to the hub node transmitting the subcarrier group. The hub node may adjust the optical power based on the power update.

Abstract: Disclosed herein are methods and systems for optimizing an optical signal in an optical network having a leaf node with a coherent optical transceiver configured to receive an optical signal continuously transmitted at a first output power from a hub node over a link. The leaf node may be provided with signal quality correction circuitry configured to determine a signal quality of the optical signal and send the signal quality to a processor of the hub node. The processor of the hub node may be configured to compare the signal quality of the optical signal to a target signal quality margin, determine that the signal quality is outside the target signal quality margin, adjust the first output power of the optical signal to a second output power different than the first output power, and continuously transmit the optical signal at the second output power.

Abstract: A transmitter can include a laser operable to output an optical signal; a digital signal processor operable to receive user data and provide electrical signals based on the data; and a modulator operable to modulate the optical signal to provide optical subcarriers based on the electrical signals. A first one of the subcarriers carriers carries first TDMA encoded information and second TDMA encoded information, such that the first TDMA encoded information is indicative of a first portion of the data and is carried by the first one of the subcarriers during a first time slot, and the second TDMA encoded information is indicative of a second portion of the data and is carried by the first one of the subcarriers during a second time slot. The first TDMA encoded information is associated with a first node remote from the transmitter and the second TDMA encoded information is associated with a second node remote from the transmitter.

Abstract: Disclosed herein are methods and systems for optimizing an optical signal in an optical network having a hub node configured to receive an optical signal comprising a plurality of subcarrier groups each having a signal quality and a transmission output power, including a method that may comprise: determining, a first subcarrier group of the plurality of subcarrier groups with a lowest signal quality lower than a required signal quality margin; determining, a second subcarrier group of the plurality of subcarrier groups that has a highest transmission output power margin, Determining, that the transmission output power margin of the second subcarrier group is above a level needed to increase the lowest signal quality by a required signal quality increase; and sending signals to a first leaf node and a second leaf node causing the first leaf node to swap transmission positions of the first subcarrier group and the second subcarrier group.

Abstract: Optical network systems and components are disclosed, including a transmitter comprising a digital signal processor that receives data; circuitry that generate a plurality of electrical signals based on the data; a plurality of filters, each of which receiving a corresponding one of the plurality of electrical signals, a plurality of roll-off factors being associated with a respective one of the plurality of filters; a plurality of DACs that receive outputs from the digital signal processor, the outputs being indicative of outputs from the plurality of filters; a laser that supplies light; and a modulator that receives the light and outputs from the DACs, and supplies a plurality of optical subcarriers based on the outputs, such that one of the optical subcarriers has a frequency bandwidth that is wider than remaining ones of the optical subcarriers, said one of the optical subcarriers carrying information for clock recovery.

Abstract: Disclosed herein are methods and systems for routing traffic. One exemplary system includes a muxponder module deployed in an optical network, the muxponder having an optical receiver, a first and second electrical port, a demultiplexer having a built-in digital cross-connect, and a processor accessing a first calculated carrier frequency to assign traffic streams associated with a first service identification code to a first and second host lane of the first electrical port, and a second calculated carrier frequency to assign traffic streams associated with a second service identification code to a third and fourth host lane of the second electrical port, and having logic to control the digital cross-connect to route a first and a second traffic stream to the first electrical port based on the first service identification code, and a third and a fourth traffic stream to the second electrical port based on the second service identification code.

Abstract: Consistent with the present disclosure, a local oscillator is provided in a receiver. The local oscillator laser a first and second mirrors and phase section and heaters are provided adjacent each portion of the laser, such that the temperature and thus the frequency of light output from the local oscillator laser may be tuned. Applying electrical power, such as a current or voltage to the phase section may result in rapid frequency tuning of light output from the local oscillator laser but over a limited frequency range. Temperature changes to the mirror sections, however, may afford frequency tuning over a wider range, but frequency tuning the mirror sections requires more time than that required to tune the phase section. Consistent with the present disclosure, a tuning method and apparatus is provided that optimizes laser tuning by selectively tuning the phase and mirror sections.

Abstract: An example system includes a first network device having first circuitry. The first network device is configured to perform operations including receiving data to be transmitted to a second network device over an optical communications network, and transmitting first information and second information to the second device. The first information is indicative of the data, and is transmitted using a first communications link of the optical communications network and using a first subset of optical subcarriers. The second information is indicative of the data, and is transmitted using a second communications link of the optical communications network and using a second subset of optical subcarriers. The first subset of optical subcarriers is different from the second subset of optical subcarriers.

Abstract: Modules for hub network elements and methods are described, including a method comprising (a) generating a partial key indicative of a unique public key associated with a hub network element in a transport network, (b) sending a partial-key message comprising the partial key and an ordered sequence to a particular network element of the ordered sequence, (c) receiving, from the particular network element to which the partial-key message was sent, the partial-key message having been modified by a unique private key associated with the particular network element, (d) repeating steps (b) and (c) for each successive network element in the ordered sequence except for a source network element and a destination network element designated by the ordered sequence, and (e) sending the partial-key message to the destination network element. The transport network comprises a plurality of network elements including the hub network element and a plurality of leaf network elements.

Abstract: Optical network systems and components are disclosed, including a transmitter comprising a digital signal processor that receives data; circuitry that generate a plurality of electrical signals based on the data; a plurality of filters, each of which receiving a corresponding one of the plurality of electrical signals, a plurality of roll-off factors being associated with a respective one of the plurality of filters; a plurality of DACs that receive outputs from the digital signal processor, the outputs being indicative of outputs from the plurality of filters; a laser that supplies light; and a modulator that receives the light and outputs from the DACs, and supplies a plurality of optical subcarriers based on the outputs, such that one of the optical subcarriers has a frequency bandwidth that is wider than remaining ones of the optical subcarriers, said one of the optical subcarriers carrying information for clock recovery.

Abstract: An example system includes a first network device having first circuitry. The first network device is configured to perform operations including receiving data to be transmitted to a second network device over an optical communications network, and transmitting first information and second information to the second device. The first information is indicative of the data, and is transmitted using a first communications link of the optical communications network and using a first subset of optical subcarriers. The second information is indicative of the data, and is transmitted using a second communications link of the optical communications network and using a second subset of optical subcarriers. The first subset of optical subcarriers is different from the second subset of optical subcarriers.

Abstract: Methods, systems, and apparatus for subcarrier modulation with radio frequency inphase-quadrature (IQ) modulators. A system includes a plurality of IQ modulators, each configured to receive an input electrical signal comprising an inphase signal and a quadrature signal, and each configured to modulate the inphase signal and quadrature signal based on one of a plurality of local oscillator signals to output a multiplexed signal. Each of the plurality of local oscillator signals is supplied by a respective one of a plurality of local oscillator circuits. A modulator circuit is configured to modulate a carrier optical signal from a laser having a frequency ?c based on the multiplexed signal to generate a modulated optical signal centered at frequency ?c and comprising a plurality of subcarriers. A center frequency of each of the plurality of subcarriers is offset from ?c by a frequency of said one of the plurality of local oscillator signals.

Abstract: Optical network systems and components are disclosed, including a transmitter comprising a digital signal processor that receives data; circuitry that generate a plurality of electrical signals based on the data; a plurality of filters, each of which receiving a corresponding one of the plurality of electrical signals, a plurality of roll-off factors being associated with a respective one of the plurality of filters; a plurality of DACs that receive outputs from the digital signal processor, the outputs being indicative of outputs from the plurality of filters; a laser that supplies light; and a modulator that receives the light and outputs from the DACs, and supplies a plurality of optical subcarriers based on the outputs, such that one of the optical subcarriers has a frequency bandwidth that is wider than remaining ones of the optical subcarriers, said one of the optical subcarriers carrying information for clock recovery.

Abstract: An example apparatus includes an optical transmitter, an optical splitter, lenses, and mirrors. The optical splitter has an input and several outputs. The input of the optical splitter is optically coupled to the transmitter, such that each of the outputs of the optical splitter is operable to supply a corresponding one of a plurality of modulated optical signals, each of which includes a plurality of optical subcarriers. Each of the lenses is optically coupled to a respective one of the outputs of the optical splitter. Each of the lenses is operable to receive a corresponding one of the modulated optical signals. Each of the mirrors is optically coupled to a corresponding one of the lenses, such that each of the mirrors is operable to direct a respective one of the modulated optical signals for transmission through free space.

Abstract: Disclosed herein are methods and systems for dynamically configuring a muxponder. One exemplary system may be provided with a muxponder module deployed in an optical network, the muxponder having an optical receiver, a first and a second electrical port, a demultiplexer having a built-in digital cross-connect, and a processor accessing a mapping table to assign traffic streams associated with a first service identification code to a first and a second host lane of the first electrical port, traffic streams associated with a second service identification code to a third and a fourth host lane of the second electrical port, and having logic to control the digital cross-connect to route a first and a second traffic stream to the first electrical port based on the first service identification code, and a third and a fourth traffic stream to the second electrical port based on the second service identification code.

Abstract: Optical network systems are disclosed, including systems having transmitters with a digital signal processor comprising forward error correction circuitry that provides encoded first electrical signals based on input data; and power adjusting circuitry that receives second electrical signals indicative of the first electrical signals, the power adjusting circuitry supplying third electrical signals, wherein each of the third electrical signals is indicative of an optical power level of a corresponding to one of a plurality of optical subcarriers output from an optical transmitter.