Granted Patent B2

US 12,615,091 · App. 18/007,647 · Granted Apr 28, 2026

Inventor: Peter Johannes Winzer (Aberdeen, NJ)

H04B10/532H04B10/2569H04B10/5161H04J14/06

Abstract

Claims (36)

1 . An apparatus for communicating optical signals modulated at a symbol rate, the apparatus comprising an optical power supply that comprises:

a light source and an electronic controller connected to the light source to cause the light source to generate a first light output having a first optical frequency and a second light output having a second optical frequency different from the first optical frequency, each of the first and second light outputs being steady during a time interval that is significantly longer than one over the symbol rate;

a polarization combiner connected to receive the first and second light outputs of the light source, and generate an optical output signal in which first and second mutually orthogonal polarization components carry light of the first and second light outputs, respectively;

a transmit module that includes at least one optical modulator configured to modulate the optical output signal from the polarization combiner; and

an optical fiber that includes one or more sections of non-polarization-maintaining fiber, in which the optical fiber is optically coupled between the polarization combiner and the transmit module, and the optical fiber is configured to transmit the optical output signal from the polarization combiner to the transmit module;

wherein the transmit module comprises:

a passive polarization splitter having an optical input port and first and second optical output ports, the optical input port being optically connected to receive the optical output signal from the polarization combiner having first and second polarization components, the first polarization component carrying light of the first optical frequency, the second polarization component carrying light of the second optical frequency;

wherein the first and second polarization components are mutually orthogonal and jointly undergoing a state-of-polarization change during a time interval, the passive polarization splitter causing light of a first fixed polarization to be directed from the optical input port to the first optical output port and also causing light of a second fixed polarization to be directed from the optical input port to the second optical output port, the first and second fixed polarizations being orthogonal to one another, the state-of-polarization change causing respective spectral compositions of the lights directed to the first and second optical ports to change during the time interval; and

a first optical modulator optically coupled to the first optical output port and configured to modulate the light of the first fixed polarization received therefrom in response to a first data signal.

2 . The apparatus of claim 1 wherein the transmit module comprises a second optical modulator optically coupled to the second optical output port and configured to modulate the light of the second fixed polarization received therefrom in response to a second data signal.

3 . The apparatus of claim 2 wherein the first and second optical modulators are optically connected to transmit the respective modulated lights through different respective optical fibers.

4 . The apparatus of claim 1 wherein at some times of the time interval, the first optical modulator receives from the first output port the first optical frequency but not the second optical frequency; and

wherein at some other times of the time interval, the first optical modulator receives from the first output port the second optical frequency but not the first optical frequency.

5 . The apparatus of claim 4 wherein at yet some other times of the time interval the first optical modulator receives from the first output port a mix of the first and second optical frequencies.

6 . The apparatus of claim 1 wherein the polarization combiner comprises at least one of a polarization beam combiner, a polarization-maintaining optical power combiner, or a polarization-maintaining wavelength multiplexer.

7 . The apparatus of claim 1 , comprising a chromatic-dispersion-compensating optical element that is configured to pre-disperse the optical output signal from the polarization combiner.

8 . The apparatus of claim 1 wherein the light source comprises:

a first laser that is configured to generate first polarized light that has the first optical frequency, wherein the first polarized light forms the first light output of the light source; and

a second laser that is configured to generate second polarized light that has the second optical frequency, wherein the second polarized light forms the second light output of the light source.

9 . The apparatus of claim 1 , wherein the light source comprises:

a laser that is configured to generate first polarized light that has the first optical frequency; and

an optical splitter that is configured to receive the first polarized light and output a first portion of the first polarized light and a second portion of the first polarized light;

wherein the first portion forms the first light output of the light source;

wherein the second portion is transmitted to a frequency shifter that is configured to frequency-shift the second portion to generate a frequency-shifted second portion that has the second optical frequency, and the frequency-shifted second portion forms the second light output of the light source.

10 . The apparatus of claim 1 , wherein the light source comprises:

a first laser that is configured to emit first polarized light at a first wavelength;

a second laser that is configured to emit second polarized light at a second wavelength;

a first optical modulator configured to modulate the first polarized light to generate first modulated polarized light;

a second optical modulator configured to modulate the second polarized light to generate second modulated polarized light;

wherein the first modulated polarized light forms the first light output of the light source, and the second modulated polarized light forms the second light output of the light source.

11 . The apparatus of claim 10 wherein the light source comprises a signal generator configured to generate electrical signals for driving the first and second optical modulators,

wherein the first laser, the first modulator, and the signal generator are configured to generate the first modulated polarized light as a first optical pulse train, and

wherein the second laser, the second modulator, and the signal generator are configured to generate the second modulated polarized light as a second optical pulse train.

12 . The apparatus of claim 10 wherein the light source comprises a signal generator configured to generate electrical signals for driving the first and second optical modulators,

wherein the first laser, the first modulator, the second modulator, and the signal generator are configured to generate the first and second modulated polarized light as dispersion pre-distorted optical signals.

13 . The apparatus of claim 10 wherein the first and second modulators are configured to modulate time stamps onto the first and second modulated polarized light.

Assignments (2)

Continuity (3)

References Cited (159)