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 technique effects survivability and security of the optical networks by encompassing conventional electronic security with an optical security layer by generating replicated versions of the input data payload at the input node, and the transmission of each of the replicated versions over a corresponding one of the plurality of links. Moreover, each of the links is composed of multiple wavelengths to propagate optical signals or optical packets, and each of the replicated versions of the data payload may be propagated over a selected one of the wavelengths in each corresponding one of the plurality of links.

Abstract: An optical transmission device wherein each device has a single dedicated channel for receiving data and destination addressing is not required. The device is formed by constructing an array of transmitter/receiver pairs (transceivers) with a processing means and a gate controller. The network is configured such that transmission on any particular receiver reserved channel results in data being sent to a predetermined node having that particular receiver reserved channel. Data passes through other nodes without pausing to check the address information in the header when the data arrives at a node as is not in the dedicated receiver reserved channel.

Abstract: An access node includes a switch that operates according to a first communication protocol. The access node is coupled by a plurality of feeder network channels to a second access node having a second switch operating according to a second communication protocol. A first distribution network port is coupled to the first switch and to a first distribution network channel bearing signals according to the first communication protocol. A second distribution network port is coupled to a second distribution network channel bearing signals according to the second communication protocol and to the second switch by one of the feeder network channels.

Abstract: An optical system includes a number of substantially identical, tunable, wavelength-preserving, optical regenerators 10. Each of the regenerators 10 is tuned to a different wavelength so that when a regenerator 10 is tuned to a given wavelength that regenerator will generate a regenerated, reshaped and retimed optical signal at the same given wavelength. The system also includes a multiplexer 32 coupled to receive and combine regenerated optical signal from each of regenerators. A filtering system (34) is provided, either internal or external to regenerators 10, to demultiplex different wavelength signals from an aggregate WDM optical signal.

Abstract: The present invention provides a method and system for monitoring a composite optical signal in an optical network. The method includes separating the composite optical signal into a plurality of subsets, each subset including a plurality of data points, and detecting the plurality of data points. The method and system in accordance with the present invention utilizes an optical performance monitor which is able to obtain the entire spectrum in a matter of milliseconds. The preferred embodiment of the optical performance monitor utilizes a plurality of separator modules to separate sets of data points of the optical signal and transfer these data points to a device for analysis. The method and system of the present invention is faster than conventional performance monitors. Because the optical performance monitor of the present invention allows the spectrum to be obtained in fractions of a second, real-time performance monitoring is provided.

Abstract: An optically implemented wide bandwidth correlation system (10) that employs a multi-mode imaging device (42) and a particular modulation format to provide both in-phase and quadrature phase correlation components in a single correlation process. The correlation system (10) includes an optical source (12) that generates a laser beam (14) that is split into a first beam path (18) and a second beam path (20). The first split beam and a first electrical signal are applied to a first modulator (22) in the first path (18) and the second split beam and the second electrical signal are applied to a second modulator (24) in the second path (20). The modulated beams are then applied to the optical imaging device (42) that causes the beams to interfere with each other within an optical cavity (48).

Abstract: A multichannel light source wavelength and strength stabilizing apparatus and a method thereof are disclosed.

Abstract: A wavelength division multiplexing (WDM) optical transmission system includes a node having a wavelength-demultiplexer, an optical switch connected to the demultiplexer, a regenerative repeater circuit connected to the switch, a controller, a monitor signal generator, and an output circuit. The demultiplexer receives a plurality of optical signals of different wavelengths and a first monitor signal having information indicative of bit rates of the optical signals. The controller identifies an optical signal which requires regenerative repeating based on the first monitor. The controller then outputs a first control signal to the switch for switching the optical signal into the regenerative repeater circuit. A second control signal is then output to the repeater circuit for controlling regenerative repeating based on the information indicative of the bit rate of the optical signal included in the first monitor signal.

Abstract: An electro-optical circuit includes optical sending and receiving components for transforming an electrical output signal to an optical output signal, and for transforming a received optical signal to an electrical input signal, respectively. The electro-optical circuit forms a module with an electro magnetically shielded case which contains the optical sending and receiving components and connection devices for an optical conductor on which the outgoing and received optical signals are transmitted. A two-sided printed circuit arrangement carries a sender for the electrical output signal and a receiver for the electrical input signal located shielded from each other on one side each by means of an electrically conducting shielding. The shielding is in connection with the case for forming three Faraday's cages, one for the sender, one for the receiver and one formed of the case in its entirety.

Abstract: Techniques for physically implementing fiber ring networks which achieve full mesh connectivity, such networks including a 2-fiber WDM ring network composed of a clockwise ring and counter clockwise ring, and a 4-fiber WDM Self-Healing Ring network. The number of wavelengths required is derived for both odd and even number of nodes on the ring. To physically set-up all required connections in the network, optimal wavelength assignment algorithms are devised so that the wavelength assignment between nodes on the ring is systematic and engenders full mesh connectivity while avoiding any possible violation of the color clash constraint. An illustrative algorithm uses a simple matrix approach for calculating the interconnection arrangement.

Abstract: Radio frequency modulated optical radiation is generated for use in a radio over fibre communications system. A semiconductor electroabsorption modulator efficiently modulates an input optical signal at harmonics of the electrical modulation frequency applied to the electroabsorption modulator. A low frequency design, and thus low cost, electroabsorption modulator is utilized to generate higher order harmonics of an electrical drive signal for use in a radie over fibre communications systems.

Abstract: An infrared signal transmitting apparatus provided by the present invention comprises an infrared light emitting device for transmitting high-speed signals, a plurality of infrared light emitting devices for transmitting low-speed signals which are distributed and laid out in such a way that, as a whole, a wide directivity is obtained, a high-speed-signal driving circuit for driving the infrared light emitting device for transmitting high-speed signals in accordance with a high-speed signal (data signal) received from a computer, a low-speed-signal driving circuit for driving the plural infrared light emitting devices for transmitting low-speed signals at the same time in accordance with a low-speed signal (remote-control signal) received from the computer, and logic means for allowing the high-speed-signal driving circuit to drive the infrared light emitting device for transmitting high-speed signals in accordance with the low-speed signal.

Abstract: The wireless optical (in particular infrared) communication system with at least one transmitter (75) and one receiver (76) comprises control means (77, 78), which dynamically adapt the data rate and/or the optical power of the transmitter in dependence of signal-to-noise ratio of the receiver. Due to this adjustment, optimized system performance is maintained even under the influence of ambient light which statistically changes the signal-to-noise ratio of the receiver. The best compromise between data rate, bit error rate and transmission range is dynamically determined. The control function is distributed between transmitting and receiving system unit. The control information is communicated via wireless optical communication.

Abstract: An optical communication system is described wherein a center (1) and distant terminals (3, 4) are connected to a fiber-optic network (2). Each of the terminals (3, 4) has a light source (5, 7) and a modulator (6, 8) connected thereto for transmitting optical signals to the center (1). Each of the modulators (6, 8) controls the respective light source (5, 7) in such a way that the light source (5, 7) emits light only within successive first time intervals T.sub.1L, T.sub.2L which are separated by second time intervals T.sub.1D, T.sub.2D and that the first time intervals T.sub.1L, T.sub.2L are shorter than the second time intervals T.sub.1D, T.sub.2D.

Abstract: A point-to-multipoint bi-directional wide area telecommunications network employing atmospheric optical communication. The network comprises a primary transceiver unit, a plurality of subscriber transceiver units and an optical router. The primary transceiver unit generates a first light beam on which it modulates first data. The primary transceiver unit atmospherically transmits the first light beam to the optical router which demodulates the first data, modulates the first data on a second light beam and transmits the second light beam to the plurality of subscriber transceiver units in multiplexed manner. The subscriber transceiver units receive the second light beam and demodulate the first data from the second light beam.

Abstract: An optical pulse signal produced by modulating a continuous laser light by means of a first pulse having a period sufficiently shorter than the atomic lifetime in the upper energy state of a rare earth doped fiber is input to an optical amplifier to be measured, while an output signal from the optical amplifier is modulated by a second pulse synchronized with the first pulse and having a phase difference relative to the first pulse which can be optionally set so that rapid phase adjustment relative to the first pulse is possible based on the phase at the time of minimum optical power. The noise figure of the optical amplifier is then measured based on, the maximum photoelectric power (P.sub.AMP +P.sub.ASE) and the minimum photoelectric power P.sub.ASE of the resultant optical signal.

Abstract: A drive circuit for an optical modulator having first and second electrodes for receiving a drive voltage. The optical modulator modulates carrier light from a light source according to the drive voltage to output modulated signal light. A terminating resistor for generating the drive voltage is connected between the first and second electrodes. A first end of a transmission line is connected to one of the first and second electrodes. A circuit for generating a drive signal is connected to a second end of the transmission line. A reflection rejecter (e.g., attenuator) for suppressing a reflected wave generating in the transmission line is provided on the transmission line. This drive circuit improves the waveform of the modulated signal light in case that the carrier light has large power.

Abstract: A broadband multiport coherent optic data switch comprises a passive optic combiner/splitter, a plurality of port units and a switch control unit connected thereto, each port unit having a coherent optic source tuned to a respective optic frequency, the output of each source carrying thereon control information, including control information received from the control unit, together with switched data, the outputs of the sources being combined and distributed to all of the plurality of port units.

Abstract: An optical switching network comprises a plurality of optical splitters coupled respectively to inlet highways for receiving wavelength-time division multiplex (WTDM) signals through the respective inlet highways, each of the multiplex signals comprising a series of WTDM signals each being identified by a unique wavelength and a unique time slot. A like plurality of sets of tunable wavelength filters are provided. The filters of each set are coupled to respective outputs of the splitters for selecting one of the WTDM signals. A like plurality of time-space switches are associated respectively with the sets of the tunable wavelength filters. Each of the time-space switches has input ports and output ports, the input ports of the time-space switch being coupled respectively to outputs of the filters of the associated set for interchanging the time slot of the selected WTDM signal with another time slot and establishing a path for the selected wavelength between the input ports and the output ports.

Abstract: The method for receiving and transmitting optical data and control information to and from remotely located receivers and transmitters in an optical location system. Wherein, the locator system tracks and locates the position of a main object having an attached transceiver. This transceiver has stored in memory selected identifying information about the object to which the transceiver is attached. The selected identifying information was received by the transceiver over it's 1-wire interface from a touch memory.