This disclosure provides a method for nonlinearly calibrating linear frequency modulation of an optical signal, an apparatus for nonlinearly calibrating linear frequency modulation of an optical signal, a computer-readable storage medium, and an electronic device. The method includes: in an i.sup.th frequency modulation cycle, obtaining a relationship between a modulation voltage signal V.sub.i(t) input into a light source and an actual frequency signal f.sub.i(t) of an optical signal output by the light source, to obtain an actual association relationship f.sub.i(V) corresponding to the i.sup.th frequency modulation cycle, where i is a positive integer; based on a target frequency modulation signal f.sub.g(t) and the actual association relationship f.sub.i(V), determining a modulation voltage signal V.sub.j(t) corresponding to a j.sup.th frequency modulation cycle, where j is i+1; and inputting a modulation voltage signal V.sub.j(t) into the light source, to implement frequency modulation of the optical signal in the j.sup.th frequency modulation cycle.

This disclosure provides a method for nonlinearly calibrating linear frequency modulation of an optical signal, an apparatus for nonlinearly calibrating linear frequency modulation of an optical signal, a computer-readable storage medium, and an electronic device. The method includes: in an i.sup.th frequency modulation cycle, obtaining a relationship between a modulation voltage signal V.sub.i(t) input into a light source and an actual frequency signal f.sub.i(t) of an optical signal output by the light source, to obtain an actual association relationship f.sub.i(V) corresponding to the i.sup.th frequency modulation cycle, where i is a positive integer; based on a target frequency modulation signal f.sub.g(t) and the actual association relationship f.sub.i(V), determining a modulation voltage signal V.sub.j(t) corresponding to a j.sup.th frequency modulation cycle, where j is i+1; and inputting a modulation voltage signal V.sub.j(t) into the light source, to implement frequency modulation of the optical signal in the j.sup.th frequency modulation cycle.

An optical-communication module includes a transceiver to communicate with another optical-communication module (another module); and a control circuit to transmit a first signal to the another module at activation of the own module, execute a first control where a second signal transmitted to the first signal is received from the another module, and execute a second control after the first control, wherein one of the first and second control is a control to adjust an intensity of a signal from the transceiver to the another module based on a feedback signal from the another module to a signal from the transceiver, and wherein the other one of the first and second control is a control causing the another module to adjust a signal intensity from the another module to the transceiver by transmitting a feedback signal to the another module to a signal from the another module.

An optical-communication module includes a transceiver to communicate with another optical-communication module (another module); and a control circuit to transmit a first signal to the another module at activation of the own module, execute a first control where a second signal transmitted to the first signal is received from the another module, and execute a second control after the first control, wherein one of the first and second control is a control to adjust an intensity of a signal from the transceiver to the another module based on a feedback signal from the another module to a signal from the transceiver, and wherein the other one of the first and second control is a control causing the another module to adjust a signal intensity from the another module to the transceiver by transmitting a feedback signal to the another module to a signal from the another module.

An optical transmission device includes: a selector configured to select a wavelength of a signal to be transmitted to an optical transmission line and output a wavelength-multiplexed signal; an adjustor configured to control a power level of the wavelength-multiplexed signal; and a controller configured to control the adjustor or the selector, wherein the selector selects a wavelength of an optical signal in a second wavelength band different from an existing first wavelength band, and when the second wavelength band is added to or removed from the optical transmission line, the controller controls power of the wavelength-multiplexed signal in the second wavelength band at a slower speed than power control in the first wavelength band.

An optical transmitter has an optical modulator having Mach-Zehnder interferometers, modulator drivers configured to drive the optical modulator by a drive signal, a low frequency generator configured to generated a low frequency signal that changes a ratio of a driving amplitude with respect to a half-wave voltage of the optical modulator, a photodetector configured to detect a portion of output light of the optical modulator, a detector configured to detect a low frequency component contained in a detected signal from the photodetector using the low frequency signal, and a bias voltage controller configured to control a bias voltage for the optical modulator such that the detected low frequency component becomes the maximum and in-phase with the superimposed low frequency signal.

An optical transmitter has an optical modulator having Mach-Zehnder interferometers, modulator drivers configured to drive the optical modulator by a drive signal, a low frequency generator configured to generated a low frequency signal that changes a ratio of a driving amplitude with respect to a half-wave voltage of the optical modulator, a photodetector configured to detect a portion of output light of the optical modulator, a detector configured to detect a low frequency component contained in a detected signal from the photodetector using the low frequency signal, and a bias voltage controller configured to control a bias voltage for the optical modulator such that the detected low frequency component becomes the maximum and in-phase with the superimposed low frequency signal.

Systems and methods of sharing optical spectrum between a plurality of users of a submarine optical system includes receiving one or more optical signals from the plurality of users of the submarine optical system, wherein each of the plurality of users are assigned a slice of optical spectrum on the submarine optical system; monitoring each of the one or more optical signals to determine compliance with one or more constraints; and adding the one or more optical signals to the submarine optical system if compliant with the one or more constraints.

Systems and methods of sharing optical spectrum between a plurality of users of a submarine optical system includes receiving one or more optical signals from the plurality of users of the submarine optical system, wherein each of the plurality of users are assigned a slice of optical spectrum on the submarine optical system; monitoring each of the one or more optical signals to determine compliance with one or more constraints; and adding the one or more optical signals to the submarine optical system if compliant with the one or more constraints.

An apparatus includes: a laser driver configured to output a laser diode current in accordance with a transmit data, a bias control code, and a modulation control code, a laser diode configured to receive the laser diode current and output a light signal, a photodiode configured to receive the light signal and output a photodiode current, a reference driver configured to output a reference current in accordance with the transmit data, the transmit enable signal, a reference bias code, and a reference modulation code, a two-fold comparison circuit configured to compare the photodiode current and the reference current and output a first decision and a second decision, and a DSP configured to adjust the bias control code and the modulation control code in accordance with the first decision and a second decision. A method provides reliable light output using the described apparatus.