摘要:
A method of phase modulating optical radiation by the steps of phase modulating the optical radiation by using a modulator having an extinction ratio in order to provide a multilevel phase shift key signal, and applying to each optical pulse a phase-shift having an absolute value depending on the extinction ratio and a sign depending, for each of the optical pulses, on the respective optical phase value. An apparatus implementing the method is also disclosed.
摘要:
There is provided an optical wavelength converter which allows the rapid and efficient shifting of information modulated on a light signal of one wavelength to a light signal of a second wavelength without the negative effects of noise and other disturbances which have proven to be problems in the prior art. The device splits a CW probe signal of a first wavelength into two components, which propagate with opposite orientations through a Kerr leg. Also propagating in the Kerr leg is a modulated drive signal at a second wavelength. These signals interact in the Kerr leg, and are recombined at an output coupler so as to create interference between the two probe components. An intensity modulated probe signal is output.
摘要:
A device and method for stabilizing the state of polarization of polarization multiplexed optical radiation including an identified channel is disclosed. The device and method comprise providing to the polarization multiplexed optical radiation a first controllable polarization transformation to generate a first transformed optical radiation; detecting a first state of polarization of a first polarized portion with respect to a first polarization parameter; controlling the first controllable polarization transformation so that the first polarization parameter has a predetermined value independent of a polarization state of the polarization multiplexed optical radiation; providing to the first transformed optical radiation a second controllable polarization transformation to generate a second transformed optical radiation; detecting a second state of polarization of a second polarized portion; and controlling the second controllable polarization transformation so that the second state of polarization has a predefined value.
摘要:
A device and method for stabilizing the polarization of polarization multiplexed optical radiation includes an identified channel which is provided with a pilot signal. The device and method are based on providing to the polarization multiplexed optical radiation a controllable polarization transformation; measuring the optical power of a polarized portion of the identified channel downstream the polarization transformation; controlling, responsively to the optical power, the controllable polarization transformation so that the identified channel downstream the polarization transformation has a predefined polarization azimuth; providing to the optical radiation downstream the polarization transformation a further controllable polarization transformation; measuring the optical power of a polarized portion of the identified channel downstream the further controllable polarization transformation; and controlling, responsively to the optical power, the further controllable polarization transformation so that the identified channel downstream the further controllable polarization transformation has a predefined state of polarization.
摘要:
An optical window signal generator which begins generation of an optical output signal in response to an optical activation pulse, and terminates generation of the optical output signal in response to an optical deactivation pulse. The rise time of the optical output signal is equal to the rise time of the optical activation pulse, and its fall time is equal to the rise time of the optical deactivation pulse.
摘要:
A method of phase modulating optical radiation by the steps of phase modulating the optical radiation by using a modulator having an extinction ratio in order to provide a multilevel phase shift key signal, and applying to each optical pulse a phase-shift having an absolute value depending on the extinction ratio and a sign depending, for each of the optical pulses, on the respective optical phase value. An apparatus implementing the method is also disclosed.
摘要:
A device and method for stabilizing the state of polarization of polarization multiplexed optical radiation including an identified channel is disclosed. The device and method comprise providing to the polarization multiplexed optical radiation a first controllable polarization transformation to generate a first transformed optical radiation; detecting a first state of polarization of a first polarized portion with respect to a first polarization parameter; controlling the first controllable polarization transformation so that the first polarization parameter has a predetermined value independent of a polarization state of the polarization multiplexed optical radiation; providing to the first transformed optical radiation a second controllable polarization transformation to generate a second transformed optical radiation; detecting a second state of polarization of a second polarized portion; and controlling the second controllable polarization transformation so that the second state of polarization has a predefined value.
摘要:
A device and method for stabilizing the polarization of polarization multiplexed optical radiation includes an identified channel which is provided with a pilot signal. The device and method are based on providing to the polarization multiplexed optical radiation a controllable polarization transformation; measuring the optical power of a polarized portion of the identified channel downstream the polarization transformation; controlling, responsively to the optical power, the controllable polarization transformation so that the identified channel downstream the polarization transformation has a predefined polarization azimuth; providing to the optical radiation downstream the polarization transformation a further controllable polarization transformation; measuring the optical power of a polarized portion of the identified channel downstream the further controllable polarization transformation; and controlling, responsively to the optical power, the further controllable polarization transformation so that the identified channel downstream the further controllable polarization transformation has a predefined state of polarization.
摘要:
A method of phase modulating optical radiation by the steps of phase modulating the optical radiation by using a modulator having an extinction ratio in order to provide a multilevel phase shift key signal, and applying to each optical pulse a phase-shift having an absolute value depending on the extinction ratio and a sign depending, for each of the optical pulses, on the respective optical phase value. An apparatus implementing the method is also disclosed.
摘要:
An optical communication system (100; 2300) comprises at least a transmitter (110) apt to emit a differential phase shift keying (DPSK) optical signal having a bit-rate equal to R, at least a receiving system (1200) for receiving the differential phase shift keying optical signal; and an optical link (130) optically connecting the transmitter and the receiving system for transmitting the DPSK optical signal from the transmitter to the receiving system, wherein the receiving system comprises a coherent optical receiving device (1205) apt to coherently receive the propagated DPSK optical signal and to emit at least one electrical signal (I) related to the received DPSK optical signal, and wherein the receiving system further comprises at least one electrical filter (270) for filtering the at least one electrical signal and having −3 dB double-side bandwidth greater than or equal to 0.44 R and lower than or equal to 0.68 R, and at least one squarer (280) for squaring the at least one filtered electrical signal. A related method for optical communication is also disclosed.