651 results about "Optical network terminal" patented technology

Component malfunctions in passive optical networks (PON) can increase bit error rates and decrease signal-to-noise ratio of communications signals. These faults may cause the receivers of the signals, either the optical line terminal (OLT) or optical network terminals (ONTs), to experience intermittent faults and / or may result in misinterpreted commands that disrupt other ONT's communication, resulting in a rogue ONT condition. Existing PON protocol detection methods may not detect these types of malfunctions. An embodiment of the present invention identifies faults in a PON by transmitting a test series of data patterns via an optical communications path from a first optical network node to a second optical network node. The test series is compared to an expected series of data patterns. An error rate may be calculated as a function of the differences between the test series and expected series. The error rate may be reported to identify faults in the PON. Through use of the embodiment, network faults can be identified and optionally automatically corrected, saving a network service provider from expending technician time and maintaining an operating state of the network.

An optical network termination (ONT) apparatus can determine its own geographic location information automatically, thereby permitting the ONT to report its geographic location to a management entity in a passive optical network (PON) automatically, without manual intervention.

The invention relates to report process method of optic network terminal, report processing includes following steps: B1. ONT receives up-bound message from user network interface which is distributed with VLAN operation distribution data property; B2. the user network interface function module of ONT operates the said VLAN Tag based on VLAN operation distribution data property, said operation of VLAN Tag are divided into three types, one is operation of VLAN marking VID and VLAN PRI, two is operation to inner layer, three is operation to outer layer, the ONT executes any type of said operation or combination of said three types. The method of the invention simplifies the operation of VLAN Tag, and the operation mode of VLAN Tag can be expanded flexibly, and it is convenient to realize various operation modes of VLAN Tag.

Locating a fault of an optical transmission line in a system which performs bidirectional optical communication between a wire center Optical Line Terminal (OLT) and plural subscriber devices, Optical Network Terminal (ONT). In this ITU defined topology, a feeder extending from the OLT is branched by a passive (non powered) splitter / coupler device into plural legs each connected to the ONT devices. The present invention encompasses a novel test apparatus and technique for fault location on Passive Optical Networks (PON) and / or Fiber of the premise Networks (FTTP), encompassing APON, BPON and EPON allowing non-service interruptive test, without damage to the ONT or OLT transceivers. The invention provides service providers the ability to locate a fault occurring on an optical transmission line while the system is actively performing bidirectional optical communication between a OLT / head-end device and plurality of ONT / subscriber devices.

The invention discloses a mine mobile communication system, which consists of an Ethernet passive optical network of a double-bus or double-loop structure, a wireless access network, a control system and an explosion-proof mobile station. The system comprises an optical link terminal, a base station controller, a ground base station, office-end equipment, passive optical splitters, explosion-proof optical network terminals, an underground explosion-proof base station, leakage antennae, base station antennae, distributed antennae and the explosion-proof mobile station, wherein the optical link terminal is connected with the ground base station and the base station controller; the explosion-proof optical network terminals are connected with the underground explosion-proof base station; the underground explosion-proof base station is connected with the leakage antennae, the base station antennae and the distributed antennae; and the explosion-proof mobile station is connected with the underground explosion-proof base station and the ground base station through a wireless interface. The mine mobile communication system has the characteristics of simple structure, flexible deployment, convenient maintenance, relatively lower cost, strong disaster resistance and anti-jamming capacity, capability of eliminating dead zones in communication and meeting requirements on a specific service environment and security for mining, and suitability for underground mobile communication in a coal mine.

An optical network terminal, which includes an optical transmitter, monitors the status of the optical transmitter, such as the output or the power consumption of the optical transmitter, to determine when the optical transmitter is illegally transmitting. When an illegal transmission is detected, the optical network terminal removes power from the optical transmitter.

In a passive optical network (PON), multiple optical network terminals (ONTS) transmit data to an optical line terminal (OLT) using a common optical wavelength and fiber optical media. Various components of the PON, including the OLT and ONT(s), can malfunction. Centralized techniques for maintaining or diagnosing fault conditions may be ineffective in large networks or in relatively small networks because of vast amounts of information and limited storage capacity for the information. Thus, fault conditions may occur and not be diagnosed due to lost or overwritten information. Therefore, a distributed approach based on information related to ranging of ONTs within the PON is employed in an example embodiment of the invention. This distributed approach can improve monitoring and diagnosis of fault conditions that may lead to instability of the PON.

An instrument for measuring bidirectional optical signals propagating in an optical transmission path between elements one of which will not transmit if continuity of the transmission path is not maintained, for example a branch path between a central offices optical line terminal (OLT) and an end-user's optical network terminal (ONT), comprises first and second connector receptacles for connecting the instrument into the path, a 2×2 coupler (32) having first and second ports (28, 30) connected to the first and second connectors (22, 24), respectively, for completing the optical transmission path, a third port (36) for, outputting a portion of each optical signal received via the first port (28) and a fourth port (34) for outputting a portion of each optical signal received via the second port (30) Detectors (38, 42, 44) coupled to the third and fourth ports convert the optical signal portions into corresponding electrical signals, which are processed to provide the desired measurements. The measurement results may be displayed by a suitable display unit (60) Where the ÖLT transmits signals at two different wavelengths, the instrument may separate parts of the corresponding optical signal portion according to wavelength and process them separately.

An optical network and a method of provisioning an optical network are described. The optical network includes a first passive optical network optical line terminal arranged to transmit a first optical signal at a first wavelength, coupled to a first port of a first optical filter arrangement, and a second passive optical network optical line terminal arranged to transmit a second optical signal at a second, different wavelength, coupled to a second port of the first optical filter arrangement. An optical coupler is connected between the second passive optical network line terminal and the second port of the first optical filter arrangement, for coupling a plurality of optical signals at a predetermined set of wavelengths from a third optical line terminal into the second port. A passive optical distribution node, for connection to a plurality of optical network terminations, is coupled to a third port of the first optical filter arrangement for distribution of optical signals between the optical line terminals and the plurality of optical network terminations. The first optical filter arrangement is arranged to pass optical signals at the first wavelength between the first port and the third port and to block optical signals at the second wavelength and the predetermined set of wavelengths between the first port and the third port, and the first optical filter arrangement is further arranged to pass optical signals at the second wavelength and the predetermined set of wavelengths between the second port and the third port and to block optical signals at the first wavelength between the second port and the third port. The second optical signal is at a faster rate than the first optical signal, and the second wavelength and the predetermined set of wavelengths are within an amplification band of a doped fibre amplifier.