Abstract: The present invention discloses an improved wavelength slicing technique for demultiplexing a composite optical signal. The technique applies a method for demultiplexing the composite optical signal for transmitting data signals over a plurality of data channels of different wavelengths represented by &lgr;1, &lgr;2, &lgr;3, &lgr;4, . . . &lgr;n where n is a positive integer. The method includes a step a) of receiving the composite optical signal into an asymmetric wavelength slicing device through a device input port. And step b) of slicing the composite signal and extracting a first composite optical signal comprising data signals transmitted in a first set of data channels &lgr;1, &lgr;a, &lgr;b, &lgr;c, . . . &lgr;n−1 through a first output port. And, extracting a second composite optical signal comprising data signals transmitted in a second set of data channels &lgr;2, &lgr;d, &lgr;e, &lgr;f, . . .

Abstract: An optical signaling header technique applicable to optical networks wherein packet routing information is embedded in the same channel or wavelength as the data payload so that both the header and data payload propagate through network elements with the same path and the associated delays. The header routing information has sufficiently different characteristics from the data payload so that the signaling header can be detected without being affected by the data payload, and that the signaling header can also be removed without affecting the data payload. The signal routing technique can overlaid onto the conventional network elements in a modular manner using two types of applique modules. The first type effects header encoding and decoding at the entry and exit points of the data payload into and out of the network; the second type effects header detection at each of the network elements.

Abstract: A clock recovery system recovers an optical clock signal from an optical data signal that is wavelength and data rate independent. The system splits the optical data signal into a first optical data signal and a second optical data signal. The system then transmits the first optical data signal and the second optical data signal in opposite directions around a fiber loop. In the fiber loop, the system modulates and amplifies the first optical data signal to generate a modulated-amplified first optical data signal. The system then recovers the optical clock signal after the modulated-amplified first optical data signal and the second optical data signal interact in the fiber loop.

Abstract: A method for linearizing optical transmission systems that includes an optical linearizer connected to the output of the optical transmitter. From the output, which includes a modulated signal and a transmitter distortion, the linearizer interacts with the wavelength chirping (d&lgr;c) of the transmitter output. More specifically, the linearizer is characterized by a wavelength dependent optical transfer curve F(&lgr;) that utilizes d&lgr;c to induce a compensation distortion. Further, the optical transfer curve F(&lgr;) has a reference wavelength (&lgr;p) and an operating point wavelength offset (&Dgr;&lgr;b). In operation, (&lgr;p+&Dgr;&lgr;b) of the optical transfer curve F(&lgr;) is aligned with (&lgr;c) of the output to establish an effective value for the compensation distortion. This compensation distortion is then added with the transmitter distortion to cancel the transmitter distortion from the modulated signal; to thereby linearize the output.

Abstract: A system for distributing multimedia information from a central office to a plurality of customer's premises each interconnected to the central office with a dedicated optical fiber includes a switch for transmitting a plurality of optical bands from the central office to each of the subscriber premises. The switch, being located in the central office and controlled by selection signals provided to or by the central office, selects a subset of first signals, either electrical or optical, and blocks others of the signals that are not contained within the subset so that the customer receives only the signals subscribed to by the customer. Each customer's premises has a receiver, coupled to the corresponding dedicated fiber, to detect the subset desired by the customer.

Abstract: A system for providing noise reduction in a long-distance telecommunications system is disclosed. A transmitter generates an optical signal. An optical link includes an optical amplifier that transmits the optical signal in a pre-established direction of propagation with substantially compensated dispersion to have an associated optical noise. A receiver is configured to receive a noisy optical signal including the transmitted optical signal and an optical noise signal. The receiver includes a photodetecting device that is configured to generate an electronic signal correlated with the noisy optical signal. The electronic signal being associated with a quality parameter (Q) that depends on said optical noise signal and distortion of the optical signal in the optical link. The optical link further includes a dispersive and nonlinear filtering device that has a normal dispersion and nonlinear component.

Abstract: Scalable and modular WDM systems to provide a number of processing functions which include, among others, signal detection, signal monitoring, wavelength conversion, signal regeneration, and generation of new WDM channels. Such WDM systems include a platform with an optical switching network and module slots for engaging WDM modules of different processing functions. Both protocol transparent and opaque WDM modules may be included in such a WDM system to provide versatile applications.

Abstract: An optical polarization encoding device has been invented which allows wavelength dependent processing of polychromatic optical signals without prior separation into narrow wavelength bands. The invention comprises a stack of variable and fixed birefringent elements which introduces, on passage through the stack, a wavelength dependent polarization onto a polychromatic optical signal of arbitrary polarization. Desired polarizations are achieved simultaneously at all wavelengths contained within the incoming signal by independently varying the birefringence and/or crystallographic orientation of each element within the stack. The encoded signal may be subsequently be processed, e.g. rerouted or attenuated, as a function of wavelength using polarization dependent devices. The encoding stack is rendered polarization insensitive by dividing the incoming optical signal, with a polarization beam splitter, into two beams of orthogonal polarization prior to passage through the stack.

Abstract: The present invention provides a strictly non-blocking WDM cross-connect that utilizes a relatively small number of wavelength interchangers. The cross-connect of the present invention comprises two fabrics and one or more wavelength interchangers that interconnect the fabrics. The fabrics are either pathwise strictly non-blocking or pathwise wide-sense non-blocking. In the former case, the WDM cross-connect is strictly non-blocking, i.e., both pathwise and wavelength strictly non-blocking. In the latter case, the cross-connect is wavelength strictly non-blocking and is pathwise wide-sense non-blocking, i.e., a routing algorithm is required to ensure that any sequence of connection requests and withdrawals can be routed without disturbing any currently routed requests.

Abstract: A wavelength division multiplex (WDM) cross-connect architecture that can selectively cross-connect, at a wavelength granularity, wavelength channels from any of a plurality of input WDM optical facilities (e.g., fibers) to any of a plurality of output WDM optical facilities. The architecture is based on multi-wavelength modules, which are capable of routing simultaneously N wavelengths. The number of required modules scales only with k2 or less (i.e., k2 modules with N complexity), where k is the number of input/output fibers. The significant reduction in complexity is traded for a decrease in blocking performance; one of the disclosed architectures is strictly non-blocking in the space domain and rearrangeably non-blocking in the wavelength domain, whereas two others are rearrangeably non-blocking in both the wavelength and space domain.

Abstract: An apparatus for broadcasting optical signals within an optoelectric computer network is disclosed. The optoelectric computer network includes multiple computers. Each of the computers includes a first fiber optic cable for sending optical signal beams and a second fiber optic cable for receiving optical signal beams. The apparatus for broadcasting optical signals within the optoelectric computer network includes a lens and a mirror array. The lens is capable of splitting an optical signal beam received from a first fiber optic cable of one of the computers into multiple optical signal beams. The mirror array, which is formed by an array of deformable mirrors, then individually directs each of the split optical signal beams to a respective second fiber optic cable of the selected remaining computers within the optoelectric computer network.

Abstract: The present invention provides a method of deactivating working fibers in an existing optical ring network or system for a cost-effective and efficient allocation of the fiber resources available in the ring network. When a working fiber is underutilized in an existing ring network, the traffic scheduled for transmission thereon is re-routed around the network away from the fiber and lockouts are applied to prevent the fiber to be removed from being protected. The fiber and associated connecting equipment thus become unused and unnecessary for traffic carrying purposes and can then be deactivated. By eliminating the need for working fibers and associated optics equipment on spans where traffic is low or non-existent, the invention can provide fiber capacity savings of up to fifty percent on each span while retaining full protection usage.

Abstract: A communications network has a plurality of nodes interconnected by an optical transmission medium. The transmission medium is capable of a carrying a plurality of wavelengths organized into bands. A filter at each node for drops a band associated therewith and passively forwards other bands through the transmission medium. A device is provided at each node for adding a band to the transmission medium. Communication can be established directly between a pair of nodes in the network sharing a common band without the active intervention of any intervening node. This allows the network to be protocol independent. Also, the low losses incurred by the passive filters permit relatively long path lengths without optical amplification.

Abstract: An optical signaling header technique applicable to optical networks wherein packet routing information is embedded in the same channel or wavelength as the data payload so that both the single-sideband modulated header and data payload propagate through network elements with the same path and the associated delays. The header routing information has sufficiently different characteristics from the data payload so that the signaling header can be detected without being affected by the data payload, and that the signaling header can also be removed without affecting the data payload. The signal routing technique can be overlaid onto the conventional network elements in a modular manner using two types of applique modules. The first type effects header encoding and decoding at the entry and exit points of the data payload into and out of the network; the second type effects header detection at each of the network elements.

Abstract: An optical signaling header technique applicable to optical networks wherein packet routing information is embedded in the same channel or wavelength as the data payload so that both the header and data payload propagate through network elements with the same path and the associated delays. The header routing information has sufficiently different characteristics from the data payload so that the signaling header can be detected without being affected by the data payload, and that the signaling header can also be removed without affecting the data payload. The signal routing technique can overlaid onto the conventional network elements in a modular manner using two types of applique modules. The first type effects header encoding and decoding at the entry and exit points of the data payload into and out of the network; the second type effects header detection at each of the network elements.

Abstract: An optical signaling header technique applicable to optical networks wherein packet routing information is embedded in the same channel or wavelength as the data payload so that both the single-sideband modulated header and data payload propagate through network elements with the same path and the associated delays. The header routing information has sufficiently different characteristics from the data payload so that the signaling header can be detected without being affected by the data payload, and that the signaling header can also be removed without affecting the data payload. The signal routing technique can overlaid onto the conventional network elements in a modular manner using two types of applique modules. The first type effects header encoding and decoding at the entry and exit points of the data payload into and out of the network; the second type effects header detection at each of the network elements.

Abstract: A multiwave optical buffer using a loop mirror of the present invention can transmit cells to a preferable node in accordance with electric control, without causing conflicts among the cells, when the cells having various waves reach a single node at the same time on a high-speed network. In order to prevent conflicts among the cells, the multiwave optical buffer using the loop mirror in accordance with the present invention stores cells having low priority and outputs the cells in a preferable time pursuant to the electric phase control, thereby improving efficiency of a high-speed optical communication network.

Abstract: The present invention consists of a method of deactivating protection fiber resources in an existing optical interconnected ring network or system. The invention uses 1:N protection principles to provide a single protection path on spans interconnecting nodes common to two or more optical rings. With the sharing of a protection fiber or channel on spans interconnecting common nodes, the present invention eliminates the need for multiple protection paths on these spans and provides substantial fiber capacity savings. According to the invention, the protection fibers and equipment deactivated can be removed or alternatively re-provisioned to provide a cost-effective and efficient allocation of the resources available in the network.

Abstract: An IrDA modulation/demodulation integrated circuit device modulates and demodulates a signal by an IrDA-complying method that meets the SIR standards. The IrDA modulation/demodulation integrated circuit device has a CRC block for performing calculation on data consisting of A, C, and I fields to calculate an FCS and appending an FCS field to the data, a data transparency control block for performing data transparency control for transmission on the data output therefrom, and a flag block for adding a BOF flag and an EOF flag at the head and the tail, respectively, of the data obtained therethrough. The IrDA modulation/demodulation integrated circuit device also has a flag block for removing the BOF and EOF flags from a demodulated signal, a data transparency control block for performing data transparency control on the basis of the data output therefrom, and a CRC block for checking for a transfer error by checking the value in the FCS field.

Abstract: An apparatus of the invention includes a non-linear optical element (NLOE) and an optical frequency discriminator (OFD). The NLOE receives an optical data signal, and introduces chirp at the leading and trailing portions of the optical pulse(s) therein or induces chirp on a continuous wave (CW) optical source coupled to the NLOE. The OFD is coupled to receive the chirped signal, and uses this signal to generate an optical clock signal. The OFD discriminates frequency content associated with chirp to enhance the optical clock signal, and may also suppress non-chirp frequency content such as may be associated with an optical carrier signal or a continuous wave (CW) signal. Related systems and methods are also disclosed.