Fiber communication systems and methods

An optical injection locking based coherent optical transmitter for a coherent optical communications network, the coherent optical transmitter comprising:

• a parent seed laser source configured to provide a low linewidth frequency channel as a parent laser signal;
• and
• a first coherent optical injection locking (COIL) subsystem including (i) a first child laser configured for COIL with a parent frequency of the parent laser signal, (ii) an optical circulator configured to inject the parent laser signal into a cavity of the first child laser, and (iii) a full-field modulator configured to output a first modulated optical signal based on an output of the first child laser routed through the optical circulator,
• wherein the first child laser is configured to receive electrical in-phase data, and wherein the first COIL subsystem further includes a second child laser configured to receive electrical quadrature data,
• wherein the first COIL subsystem further includes a first optical coupler disposed between (i) the optical circulator and the first child laser, and (ii) the optical circulator and the second child laser,
• wherein the first COIL subsystem further includes a first phase shifter disposed between the first optical coupler and the second child laser, and
• wherein the first phase shifter is configured to implement a 45-degree one-way phase shift.

An optical communication network, comprising:

• an optical hub including:
• a parent seed laser source;
• and
• a plurality of full-field coherent optical transmitters disposed proximate the optical hub, wherein each full-field transmitter of the plurality of full-field coherent optical transmitters is configured to transmit a downstream coherent optical signal using a center frequency of a parent signal from the parent seed laser source, and includes (i) a first child laser injection locked to the center frequency of the parent signal, (ii) a first stage configured to implement amplitude modulation for the first child laser, and (iii) a second stage configured to implement phase modulation on an output of the first stage to generate a full-field coherent optical signal, wherein the phase modulation of the second stage is orthogonal to the amplitude modulation of the first stage;
• a receiver;
• and
• an optical transport medium operably connecting the plurality of full-field coherent optical transmitters to the receiver.