Abstract: The present invention relates to an optical coherence tomography analysis method, comprising: Providing a Swept Source Optical Coherence Tomography system (SS-OCT), the SS-OCT system including: a light source, tunable over a spectral band, that generates a coherent light signal; an optical interferometer for dividing the coherent light signal into a reference arm leading to a reference reflector and a sample arm leading to a sample; an optical element to selectively direct a sample light signal exiting the sample arm to a specific portion of the sample, so that for each selection in the optical element a different specific portion of the sample is illuminated; an optical detector for detecting an interference signal generated by a combination of reference and sample returning signals from the reference arm and from the sample arm, reflected by the reference reflector and the sample, respectively; Wherein, for the same selection operated at the optical element level illuminating a specific portion of the

Abstract: In a telecommunication network, a modular expandable gateway connects a local area network to a wide area network and includes a base module and a plurality of add-on modules arranged in one or more stacks, the base module and the add-on modules including respective encryption/decryption engines to exchange secure information with each other, thus frustrating any possible fraudulent interception of the information at the module interconnections.

Abstract: An optical amplifier (1), and a related optical amplification method, comprising an optical path (2) having an input end (3) and an output end (4), a first erbium doped optical fiber (5) placed along the optical path, a first gain flatting filter (6) placed along the optical path downstream the first erbium doped optical fiber, a second erbium doped optical fiber (7) placed along the optical path downstream the first gain flatting filter, a second gain flatting filter (8) placed along the optical path downstream the second erbium doped optical fiber, a third erbium doped optical fiber (9) placed along the optical path downstream the second gain flatting filter, and an optical pump (10) optically coupled to the optical path so as to optically pump at least the first and the third erbium doped optical fiber.

Abstract: An optical amplifier (1), and a related optical amplification method, comprising an optical path (2) having an input end (3) and an output end (4), a first erbium doped optical fiber (5) placed along the optical path, a first gain flatting filter (6) placed along the optical path downstream the first erbium doped optical fiber, a second erbium doped optical fiber (7) placed along the optical path downstream the first gain flatting filter, a second gain flatting filter (8) placed along the optical path downstream the second erbium doped optical fiber, a third erbium doped optical fiber (9) placed along the optical path downstream the second gain flatting filter, and an optical pump (10) optically coupled to the optical path so as to optically pump at least the first and the third erbium doped optical fiber.

Abstract: Optical amplification stage (1) for OTDR monitoring, comprising a first (2a) and a second optical signal path (2b), a first (3a) and a second optical amplifier (3b), a first optical coupler (4a) placed along the first optical signal path downstream the first optical amplifier, a second optical coupler (4b) placed along the second optical signal path downstream the second optical amplifier, an optical by-pass path (5) optically connecting the first and the second optical coupler, a first (11a) and a second optical reflector (11b) optically connected to respectively the first and second optical coupler, and an optical filter (10) placed along the optical by-pass path which has attenuation high on the whole WDM band and low at the OTDR wavelength(s).

Abstract: A solar concentrator (1) having a longitudinal axis of extension (3) and a cross-section at right angles to the longitudinal axis substantially equal for a continuum of cross-sections, and comprising a reflective system (6) and a refractive system (7), the reflective system forming an optical inlet (8) and an optical outlet (9) and comprising two semi-portions positioned specularly relative to the plane of symmetry, where the cross-section profile of the refractive system is a triangle (11) having a base (12) at the optical outlet (9) and apex (13) on the axis of symmetry (5), where the cross-section profile of each semi-portion of the reflective system comprises a segment (18) in the shape of a parabola having an axis (20) forming with the axis of symmetry an acceptance angle (?0) greater than zero and a focus (F) on the axis of symmetry, and where the focus falls inside the triangle.

Abstract: A solar concentrator (1) having a longitudinal axis of extension (3) and a cross-section at right angles to the longitudinal axis substantially equal for a continuum of cross-sections, and comprising a reflective system (6) and a refractive system (7), the reflective system forming an optical inlet (8) and an optical outlet (9) and comprising two semi-portions positioned specularly relative to the plane of symmetry, where the cross-section profile of the refractive system is a triangle (11) having a base (12) at the optical outlet (9) and apex (13) on the axis of symmetry (5), where the cross-section profile of each semi-portion of the reflective system comprises a segment (18) in the shape of a parabola having an axis (20) forming with the axis of symmetry an acceptance angle (?0) greater than zero and a focus (F) on the axis of symmetry, and where the focus falls inside the triangle.

Abstract: Optical amplification stage (1) for OTDR monitoring, comprising a first (2a) and a second optical signal path (2b), a first (3a) and a second optical amplifier (3b), a first optical coupler (4a) placed along the first optical signal path downstream the first optical amplifier, a second optical coupler (4b) placed along the second optical signal path downstream the second optical amplifier, an optical by-pass path (5) optically connecting the first and the second optical coupler, a first (11a) and a second optical reflector (11b) optically connected to respectively the first and second optical coupler, and an optical filter (10) placed along the optical by-pass path which has attenuation high on the whole WDM band and low at the OTDR wavelength(s).

Abstract: A method of filtering an optical signal includes operating an optical filter having resonators, each having a respective free spectral range and a respective resonance falling within a first frequency band, first tuning at least one resonator with respect to at least another resonator to obtain a separation between any resonance of at least one resonator falling within an optical bandwidth with respect to a resonance of at least another resonator nearest to the any resonance, second tuning all the resonators of the optical filter so as to move all respective resonances by a respective frequency interval greater than a frequency spacing, and third tuning the at least one resonator and the at least another resonator such that a further respective resonance of each one of the resonators falls within a second frequency band, different from the first frequency band.

Abstract: An optical transmission system having an optical source, an optical dispersion compensation filter optically connected to the optical source, and a control system. The optical source generates a modulated optical signal having an optical spectrum and a value of dispersion robustness. The optical dispersion compensation filter has at least two cascaded optical resonators and a periodic transfer function rigidly translatable in the frequency spectrum to obtain translation in frequency of the transfer function without a substantial change in shape, and characterized by a free spectral range. The control system acts on the optical dispersion compensation filter in order to rigidly translate the transfer function along the frequency spectrum in first and second positions in the frequency spectrum. The translation of the transfer function between the first and the second positions is smaller than the free spectral range.

Abstract: Systems and methods for generating spectrally efficient modulated optical signals are provided. Capacity of WDM optical communication links may be increased dramatically without changing the WDM channel plan thus minimizing modifications to optical amplifiers and passive optical components. A vestigial sideband (VSB) optical signal may be generated by filtering an amplitude modulated (AM) signal using a filter having a center frequency locked to the transmission frequency of a laser.

Abstract: Optical transmission system (200) comprising: an optical source (210) adapted to generate a modulated optical signal having an optical spectrum and a dispersion robustness; an optical dispersion compensation filter (250) optically connected to the optical source, comprising at least two cascaded optical resonators and having a periodic transfer function that is rigidly translatable in the frequency spectrum and characterized by a free spectral range (FSR); a control system (270; 280; 260) adapted to act on the optical compensation filter in order rigidly to translate said transfer function along the frequency spectrum in a first and in a second position in such a way that: in a first position in the frequency spectrum of said transfer function, the mean chromatic dispersion weighted over said optical spectrum of the modulated signal is greater, in absolute value, than the value of dispersion robustness; in a second position in the frequency spectrum of said transfer function, the mean chromatic dispersion wei

Abstract: The method for filtering an optical signal comprising a plurality of channels lying on a grid of optical frequencies equally spaced by a frequency spacing and occupying an optical bandwidth, comprises: a) operating an optical filter comprising a plurality of resonators each having a respective free spectral range, wherein a first resonator of the plurality is optically coupled to the optical signal and the remaining resonators are optically coupled in series to the first resonator, so that a respective resonance of each one of the plurality of resonators falls within a first frequency band having bandwidth less than or equal to 15 GHz; b) operating the optical filter so as to obtain a separation between any resonance of at least one resonator falling within the optical bandwidth with respect to a resonance of at least another different resonator nearest to the any resonance, the separation being greater than or equal to 150 GHz and no more than 1 THz; c) tuning all the resonators of the optical filter so as t

Abstract: In a telecommunication network, a modular expandable gateway connects a local area network to a wide area network and includes a base module and a plurality of add-on modules arranged in one or more stacks, the base module and the add-modules including respective encryption/decryption engines to exchange secure information with each other, thus frustrating any possible fraudulent interception of the information at the module interconnections.

Abstract: Point-to-point link for the transmission of digital signals includes two opto-electronic conversion apparatuses and an optical cable including at least one optical fiber having two terminal portions, each opto-electronic conversion apparatus including an opto-electronic device optically coupled to a respective terminal portion between the two terminal portions of the at least one optical fiber, wherein at least one of the two opto-electronic conversion apparatuses is adapted to keep the respective terminal portion of the optical fiber in bent position with a bending radius R, where 1.5 mm?R?2.5 mm, and to keep the respective opto-electronic device optically coupled to the bent terminal portion in order to allow the transmission of the digital signals between the optical fiber and the at least one of the two opto-electronic conversion apparatuses; and at least the bent terminal portion of the at least one optical fiber is such as to satisfy the following relationship r/R<0.

Abstract: Point-to-point link for the transmission of digital signals includes two opto-electronic conversion apparatuses and an optical cable including at least one optical fiber having two terminal portions, each opto-electronic conversion apparatus including an opto-electronic device optically coupled to a respective terminal portion between the two terminal portions of the at least one optical fiber, wherein at least one of the two opto-electronic conversion apparatuses is adapted to keep the respective terminal portion of the optical fiber in bent position with a bending radius R, where 1.5 mm?R?2.5 mm, and to keep the respective opto-electronic device optically coupled to the bent terminal portion in order to allow the transmission of the digital signals between the optical fiber and the at least one of the two opto-electronic conversion apparatuses; and at least the bent terminal portion of the at least one optical fiber is such as to satisfy the following relationship r/R<0.

Abstract: At a receiver a 20 Gbit/s soliton bit stream (20) is demultiplexed into two 10 Gbit/s bit streams (22a, 22b) using a 2-way splitter (6), a clock extraction circuit (4), and a pair of polarization insensitive amplitude modulators (8a, 8b) exhibiting positive chirp. The outputs of the modulators are fed to detectors (7a, 7b) via lengths (9a, 9b) of optical fiber exhibiting normal dispersion thereby producing bit streams (23a, 23b) with increased mark/space ratio and reduced timing jitter.

Abstract: An amplification architecture for WDM receiver systems. The WDM channel grid is divided into groups of adjacent channels. A separate optical amplifier is provided for each channel with a single pump being shared among the channels of each group. The gain experienced by channels of a given group may be adjusted by varying the power of the group's pump. This approach allows equalization of received channel power such that all channels fall within the desired dynamic range. The amplification architecture may be implemented in a space-efficient manner at low cost.

Abstract: An approach for automatic Raman gain and tilt control for a WDM (Wavelength Division Multiplexing) optical communication systems is disclosed. An optical fiber carries a plurality of optical signals, in which at least one of the optical signals are reference signals. An optical gain unit (e.g., Raman pump unit) couples to the optical fiber and adjusts the reference signals to compensate, in part, for losses associated with the optical fiber and gain tilt accumulation. Upon detecting and analyzing the reference signals, a controller controls the optical gain unit and outputs a control signal to the optical gain unit based upon the analyzed reference signals. An optical amplifier is connected to the optical fiber and amplifies the optical signals. The optical gain unit provides a nearly constant power per channel at an input of the optical amplifier.

Abstract: Soliton or soliton-like optical pulses with characteristics adapted to propagation in an optical line for RZ type transmission are generated by modulating a continuous optical signal (1) by means of a modulator (2) which is substantially devoid of chirping, in which the modulator drive signal comprises at least one frequency (4) and one harmonic (5) thereof superimposed on each other (7). A high-speed optical transmission system is rendered independent of the type of transmitter or of signals sent to it if it comprises an adaptation unit (32) receiving the original optical pulses (30) and capable of generating corresponding pulsed signals (63) of RZ type.