摘要:
A device (D) is dedicated to optical switching in a switching node (NC) of a transparent optical network. This device (D) comprises i) at least one input port adapted to be coupled to an upstream optical line (FE1-FE4) dedicated to the transport of multiplexed channels, ii) at least one exit point, iii) switching means (MC) coupling each input port at least to each exit point, and iv) processing means (MT1-MT4) adapted to add to the channels that reach each input port a signature including first information representative of that switching node (NC), and where applicable the input port that received them.
摘要:
An all-optical clock recovery system for recovering the clock from a received optical signal with a short response time and without patterning effects includes a first optical clock recovery device adapted to supply a first optical clock signal in response to the received optical signal and a second optical clock recovery device adapted to supply a second optical clock signal in response to the first optical clock signal. Applications include regenerating optical packets in asynchronous optical packet-switched telecommunication networks.
摘要:
To format a power modulated input optical signal, at the same time as improving its power dynamic range and the extinction rate of the output signal, a device for formatting binary optical signals includes a first stage for supplying a modulating signal having stabilized high levels as a function of the input signal and an interferometer structure second stage receiving the modulating signal and a probe wave power modulated in phase opposition to the modulation of the modulating signal. The low and high levels of the probe wave are stabilized. Applications include optical transmission.
摘要:
A method of operating a WDM transmission system (1) with at least one transmitter (4) and at least one receiver (6) connected by means of a dispersive transmission line (8). The proposed method comprises the successive steps of successively: a) setting a tuneable dispersion pre-compensation value at a transmitter-side Tuneable Dispersion Compensation Module (5) in operative connection with the transmitter to a first predetermined value (PRE°); b) setting or adjusting a tuneable dispersion post-compensation value at a receiver-side Tuneable Dispersion Compensation Module (7) in operative connection with the receiver to a second value (POST°) in order to optimise at least one characteristic (monitored performance like BER, eye opening, Q factorBER) of a transmitted signal at the receiver; and then c) simultaneously tuning the transmitter-side Tuneable Dispersion Compensation Module and the receiver-side Tuneable Dispersion Compensation Module with opposite respective dispersion shifts in order to further optimise said characteristic of the transmitted signal.
摘要:
An optical fiber comprising an optical core enclosed in optical cladding, both made of a silica-based material, and a protective layer constituted by amorphous boron. The amorphous boron layer is deposited on a non-crystalline carbon which is itself deposited directly on the optical cladding. Also, a method is provided for depositing an amorphous boron layer on an optical fiber and includes a deposition step of depositing a layer of carbon on the fiber, followed by a subsequent step of depositing the amorphous boron protective layer chemically from the vapor phase on the layer of carbon.
摘要:
A wavelength converter for binary optical signals includes an interferometer structure (110) for generating an output signal by modulating a received local signal (LS) according to the modulation of a fUrther received first input signal (IS 1). When such interferometer structures (110) are operated in a standard mode it is known in the art to control the power of the input signal such that the extinction ratio of the output signal is kept minimal. The invention also controls the power of the input signals to achieve the minimal extinction ratio when the wavelength converter and in particular the interferometer structure (110) is operated in a differential mode receiving two input signals.
摘要:
An optical receiver (5) for an optical network (2) comprises a dispersion compensation module (7) for adjusting an amount of chromatic dispersion of optical signals transmitted through the optical network (2) and is characterized in that a nonlinear optical element (13) for spectral broadening of a dispersion probe signal transmitted through the optical network (2) is arranged in a measuring path (11) downstream of the dispersion compensation module (7), and a power measuring means (15) for measuring an average power of the optical dispersion probe signal over a predetermined frequency range is arranged downstream of the nonlinear optical element (13) in the measuring path (11).
摘要:
A method of applying an amorphous boron-based protective coating to an optical fiber comprising an optical core enclosed in optical cladding, both made of a silica-based material, wherein the boron is applied to the surface of said optical fiber chemically from the vapor phase at a temperature lying in the range 1050.degree. C. to 1250.degree. C., by reducing boron chloride BCl.sub.3 by means of hydrogen H.sub.2. The amorphous boron protective coating imparts mechanical protection to the fiber, and enhanced abrasion resistance, enabling the fiber to be used in optical cables of high capacity and that are highly compact. The thickness of the resin coating can be about half that required when a carbon protective coating is used, and can even be eliminated. The coating further provides sealing properties comparable to those provided by a carbon coating.
摘要:
A method of operating a WDM transmission system with at least one transmitter and at least one receiver connected by means of a dispersive transmission line. The proposed method comprises the successive steps of successively: a) setting a tunable dispersion pre-compensation value at a transmitter-side Tunable Dispersion Compensation Module in operative connection with the transmitter to a first predetermined value (PRE°); b) setting or adjusting a tunable dispersion post-compensation value at a receiver-side Tunable Dispersion Compensation Module (7) in operative connection with the receiver to a second value (POST°) in order to optimize at least one characteristic (monitored performance like BER, eye opening, Q factor BER) of a transmitted signal at the receiver; and then c) simultaneously tuning the transmitter-side Tunable Dispersion Compensation Module and the receiver-side Tunable Dispersion Compensation Module with opposite respective dispersion shifts in order to further optimize said characteristic of the transmitted signal.
摘要:
The present invention propose to use an optical multiplexer associated with an optical clock as a wavelength converter. Each RZ coded tributary will be carried by a single wavelength (channel) passively interleaved with the others without interferometric interaction hence achieving a not necessarily perfect OTDM. This input data stream as optical data signal composed of different wavelengths is then launched on at least one data access of said optical multiplexer used as a wavelength converter. An optical clock at the desired bit-rate is launched on the probe access of said optical multiplexer synchronously to the multi-wavelength data stream. At the output, the initial clock wavelength is converted on data signal using the gain conversion property of the optical multiplexer. In such a way, a data stream of substantially higher bit-rate is obtained while due to a very precise synchronization a lost of data is minimized.