2568 results about "Fiber-optic communication" patented technology

A method and apparatus for switching AC appliances and lights of residences and other automation systems through SPDT or DPDT relays connected in electrical circuit with SPDT or DPDT switch including a current sensor and/or a status sensor. The operating key of the relay and the key lever of the electric switch can each be used for operating a dedicated appliance or light, a group of appliance and lights and all appliance and/or lights including scenarios setup via the many well known two way, three way or four way light switches, by operating the switch lever or key in multi steps. The SPDT or DPDT relays are operated via RF, IR and fiber optic communicating two way signal for operating the lights and reporting statuses.

A multi-port optical connection terminal for use as a branch point in a fiber optic communications network at a distance from a mid-span access location provided on a distribution cable having a plurality of optical fibers. The multi-port terminal includes a base and a cover affixed to the base. A stub cable port formed through one of the base and the cover receives a stub cable having at least one optical fiber extending continuously from the multi-port terminal to the mid-span access location. A first end of the optical fiber is optically connected to a respective optical fiber of the distribution cable at the mid-span access location and a fiber optic connector is mounted upon the second end. At least one connector port is provided on the multi-port terminal for receiving the fiber optic connector and a connectorized end of a fiber optic drop cable extending from the multi-port terminal.

The present invention allows remote antenna units for radio frequency signal transmission and receipt to operate without the requirement for remote electrical power supplies or for connecting cables that incorporate electrical conductors. According to an aspect of the present invention, an optical communications system employing radio frequency signals comprises a central unit; at least one remote unit having at least one optoelectronic transducer for converting optical data signals to radio frequency signals and converting radio signals to optical signals and at least one antenna to receive and send radio frequency signals; at least one optical fiber data link between the central unit and the remote unit for transmitting optical data signals therebetween; and at least one optical fiber power link between the central unit and the remote unit for providing electrical power at the remote unit.

A network interface device (NID) for a fiber optic communications network is provided for housing optical, electrical and/or coaxial connections and active and/or passive components. The NID includes a base and a movable panel defining a connections area and a components area. In one embodiment, a first base defines a first compartment for housing the panel and a second base defining a second compartment for storing drop cable slack, the first base being movably attached to the second base to provide access to the drop cable slack without disturbing the connections. In another embodiment, the panel defines a first compartment for optical and electrical connections and a second compartment for active and passive components, the second compartment being accessible to only the service provider. In another embodiment, the panel is removable and interchangeable to permit the service provider to upgrade the services or to expand services provided to a subscriber.

A system for powering a network element of a fiber optic communication network. When communication data is transferred between a central office (CO) and a subscriber gateway using a network element to convert optical to electrical (O-E) and electrical to optical (E-O) signals between a fiber from the central office and copper wires or coax cable from the subscriber gateway, techniques related to local powering of a network element or drop site by a subscriber or customer remote device or gateway are provided. Certain advantages and/or benefits are achieved using the present invention, such as freedom from any requirement for additional meter installations or meter connection charges. Additionally the system is free of monthly meter charges and does not require a separate power network.

The present disclosure provides a polarization multiplexed transceiver, including: a transmitter; a receiver; circuitry within the transmitter configured to insert pilot tones as a reference state of polarization for a polarization multiplexed signal; and circuitry within the receiver configured to de-multiplex the polarization multiplexed signal using the pilot tones. The transmitted signal is constructed in such a manner as to facilitate the division of the receiver processing between the analog and digital domains such that the implementation may be simultaneously both highly spectrally efficient and power efficient.

A fiber optic distribution cable assembly includes a distribution cable having at least one predetermined mid-span access location and a tether for mitigating cable length errors at the mid-span access location in a pre-engineered fiber optic communications network. At least one optical fiber of the distribution cable is accessed at the mid-span access location and optically connected to an optical fiber disposed within the tether. Preferably, the first end of the tether is attached to the distribution cable by overmolding the mid-span access location with a flexible encapsulant material. The end of the optical fiber of the tether may be splice-ready or connectorized at the second end of the tether and protected within a crush resistant tube. Alternatively, the second end of the tether may terminate in an optical connection terminal defining at least one optical connection node, or may terminate in a linear chain of articulated optical connection nodes.

Optical network termination systems, devices and methods including an optical network terminal (ONT) having a processor in communication with an external optical fiber. The ONT processors further in communication with a wireless access point and at least one electrically conductive internal transport medium, both providing for the communication of telecommunication signals with devices located within a customer premises. The wireless access point and in certain instances the processor are back powered over the electrically conductive internal transport medium from AC power within the premises. In certain embodiments, the wireless access point communicates with devices within the premises over a distributed antenna.

The invention relates to a flat telecommunication cable in which optical fibers are positioned within micromodules. The micromodules are coupled to a surrounding, ribbon-like cable jacket, thereby preventing the micromodules from sagging within the cable during vertical installations. The invention also relates to a method of extracting optical fibers from such a cable.

The present invention provides optical fiber communication cable assemblies useful for separating and conveying individual fibers from a multiple optical fiber cable to connectors in a protective manner. The optical fiber cable assembly is suitable for outdoor use and includes a (i) cable with multiple optical fibers; (ii) a furcation unit attached to the cable for directing individual optical fibers from the cable to furcation legs; and (iii) multiple furcation legs receiving at least one of the optical fibers. The furcation legs include (i) a buffer tube surrounding the optical fiber; (ii) strength members surrounding the buffer tube; and (iii) a jacket surrounding the strength members. The furcation legs typically exhibit a tensile rating of at least about 50 pounds (lb_f), more typically 100 pounds (lb_f) or more. Moreover, the furcation legs typically exhibit total shrinkage of less than about 2 percent when cycled from +23° C. to −40° C. to +70° C. to −40° C.

Embodiments of the present invention exploit the existing capabilities of the Ethernet Passive Optical Network (EPON) MAC layer, designed for fiber optics communications, to provide a low cost MAC layer with upper layer connectivity over a hybrid fiber coaxial (HFC) network. In particular, embodiments allow for the EPON MAC to be used end-to-end (i.e., from an optical line terminal (OLT) to a coaxial network unit (CNU)) in a HFC network, thereby fully leveraging the packet processing capabilities, QoS functions, and management features of the EPON MAC. Furthermore, embodiments enable unified provisioning and management for both fiber and coaxial network units in a HFC network.

Patch panel assemblies (150) that contain patch panel modules (50) for use in optical fiber telecommunication systems are disclosed. One of the patch panel assemblies includes a front mounting frame (210F) and at least one internal mounting frame (210I) that support a plurality of patch panel modules. The patch panel assembly also includes a hinge assembly (224) configured allow bend-insensitive fiber cables (70) to be routed therethrough. One of the patch panel assemblies includes a housing (152) with a drawer (270) that supports a plurality of patch panel modules. The patch panel modules employ bend-insensitive optical fibers (12C) to connect front and rear ports (92, 98) so that the patch panels have a reduced size as compared to conventional patch panel modules. The patch panel assemblies include a cable distribution box (300) that can store excess cable and that assists in routing bend-insensitive fiber optic cables within the patch panel assembly interior (200) in order to connect to select patch panel module jacks (90).

A source and/or method of generating quantum-correlated and/or entangled photon pairs using parametric fluorescence in a fiber Sagnac loop. The photon pairs are generated in the 1550 nm fiber-optic communication band and detected by a detection system including InGaAs/InP avalanche photodiodes operating in a gated Geiger mode. A generation rate>10³ pairs/s is observed, a rate limited only by available detection electronics. The nonclassical nature of the photon correlations in the pairs is demonstrated. This source, given its spectral properties and robustness, is well suited for use in fiber-optic quantum communication and cryptography networks. The detection system also provides high rate of photon counting with negligible after pulsing and associated high quantum efficiency and also low dark count rate.

An adjustable tether assembly for a fiber optic distribution cable includes a tether cable and an overmolded housing secured at the end of the tether cable having at least one connector port. The tether assembly is attached to the distribution cable such that the position of the connector port is adjustable along the length of the distribution cable for mitigating differences between the pre-engineered span length distance and the actual span length distance following installation of the distribution cable. A method for mitigating a span length measurement difference in a pre-engineered fiber optic communications network is provided that includes optically connecting an adjustable tether assembly at a mid-span access location of a fiber optic distribution cable and positioning a housing secured at the free end of a tether cable having at least one connector port at a desired location in the network to compensate for the span length measurement difference.

A cable assembly configured to be deployed in a fiber optic communications network includes a pulling grip body disposed at an upstream end of the cable assembly and a preconnectorized distribution cable having a plurality of optical fibers and at least one strength member. The pulling grip body includes a pulling loop that is mechanically coupled to the strength member to permit a high tensile load to be transferred to the distribution cable without inducing relative movement between the cable elements. The pulling grip body is preferably formed by overmolding the pulling loop and the strength member with a flexible encapsulant material. At least one multifiber connector is terminated to optical fibers of the distribution cable at the upstream end. The pulling grip assembly and the preconnectorized distribution cable have a low profile capable of being pulled through a conduit.

Methods, apparatus, and systems for an optical communication channel. A data signal is preconditioned prior to transmission over a fiber optic cable to minimize signal distortion and transmitted over a fiber optic cable. Preconditioning may include none, one or more, or all of the following: encoding the data signal using a run length limited code, correlating bits of the data signal, and spreading out the pulses in the time-domain in the data signal. The pulse spreading function can be implemented either in the electrical domain prior to the electrical-to-optical conversion; in the optical domain during and/or after the electrical-to-optical conversion; or a combination of both. During reception, the data signal and clock are recovered. Recovery may include maintaining an amplitude in an electrical signal, filtering the electrical signal, shaping the electrical signal, and removing distortions and intersymbol interference (ISI) from the received electrical signal.

An optical receiver comprising a frontend configured to receive an optical signal and convert the optical signal into a plurality of digital electrical signals comprising a plurality of spectrally shaped subcarrier signals carrying symbol mapped data information, and a digital signal processor (DSP) unit coupled to the frontend and configured to receive the digital signals from the frontend, demulitplex the digital signals into the subcarrier signals, and compensate chromatic dispersion (CD) for each of the subcarrier signals by applying an equalizer, wherein each of the subcarrier signals is associated with a unique tone frequency and a unique spectral shape. Also disclosed is an optical transmitter comprising a digital signal processor (DSP) unit configured to map data symbols onto a plurality of electrical subcarrier signals that are non-overlapping and spectrally shaped in a frequency domain.

A plurality of optical communications systems including a SPW modulator are described. The communications systems include an optical transmitter coupled to an optical fiber communications link which carries a optically modulated information signal to an optical receiver. The laser transmitter includes a laser light source which is optically coupled to a SPW modulator which has been particularly adapted for broadband communications by selecting its transfer characteristic and modulation structure. A broadband signal containing a plurality of information channels, for example CATV channels, is applied to it modulator electrodes. The modulation signal varies the power coupling between the guided laser light source signal and a SPW in the modulator. The result is an intensity modulated optical signal that is output to the optical fiber for transmission to the optical receiver of the system. Alternatively, the communications system includes a high power laser coupled to an optical splitter to divide its output power in two or more optical source outputs. Each optical source output is then used to drive an associated SPW modulator. Each of the modulators receives a broadband signal with which to modulate its optical source. After modulation, the modulated lightwave from a modulator is coupled to a corresponding optical fiber for carriage to an optical receiver. In this manner, several broadband information signals can be communicated over the system using only one laser source. A net benefit from using one higher power laser, rather than several lower power ones, is one of cost, purity and similarity of the several signals. This configuration is enhanced by the lower loss and higher linearity of the SPW modulators. Further, several WDM embodiments including those having serially cascaded SPW modulators are provided. The transfer characteristic of the SPW modulators are tailored to either be more efficient for an analog or a digital modulation signal by adding or subtracting grating effects.