A method and apparatus is proposed for accurately evaluating the performance of optical transmitters under test conditions (such as high bit-rate modulation formats) that compromise the operability of standard test equipment used for this purpose. The proposed apparatus and method are similar to the elements associated with existing testing standards based on an optical eye diagram, with an important distinction that allows for accurate measurements of the transmitter's performance to be made. In particular, the sampling point for collecting eye diagram data samples in the inventive arrangement is shifted by half a period with respect to the conventional mid-eye sampling point, eliminating the need to include representative reference equalizer in the test equipment and providing an evaluation not influenced by the test equipment, resulting in a more accurate measurement of transmitter-related distortions.

A control apparatus for registering a connection state between component devices constituting a distributed optical transmission apparatus in a database includes: a device setting unit which performs setting such that light is output from a component device that is a connection source; and a registration processing unit which acquires a light reception level of each port in each component device on a side receiving the light, identifies a port having a light reception level higher than light reception levels of other ports, and registers a component device having the identified port and the identified port in the database as a connection destination of the component device that is the connection source.

An Optical Time Domain Reflectometer (OTDR) module obtains Optical Return Loss (ORL) of a fiber plant. Calibration information is obtained of at least internal OTDR reflections associated with the OTDR module. The OTDR module is connected to the fiber plant. An ORL response is measured due to reflections of an ORL signal transmitted from the OTDR module along the fiber plant, and a peak OTDR response is measured in response to reflections of an OTDR signal transmitted from the OTDR module along the fiber plant. A corrected ORL response of the fiber plant is determined by: using the measured peak OTDR response (e.g., peak value or area under the peak) and the calibration information to calculate the calculated ORL due to internal reflections, and then adjusting the measured ORL response by the calculated ORL to represent the corrected ORL of the fiber plant.

A data communication network includes a plurality of network nodes coupled together via optical links and a network controller. Each network node includes a reflectometry analyzer that provides a characterization of physical properties of the optical links coupled to the associated network node. The characterization for each particular optical link provides a unique fingerprint of the physical properties of the particular optical link. The network controller determines a network path between a first network node and a second network node, wherein the network path traverses a first optical link, receives a first fingerprint for the first optical link from a first reflectometry analyzer, defines a signature for the path, the signature including the first fingerprint, receives a second fingerprint for the first optical link from the first reflectometry analyzer, the second fingerprint being different from the first fingerprint, and determines that the network path is not secure based upon the difference between the first fingerprint and the second fingerprint.

Aspects of the present disclosure describe a method for estimating mode field distribution in optical fibers from guided acoustic-wave Brillouin scattering wherein light for which the optical mode-field distribution is determined remains in the optical fibers and the distribution is made for light inside the fiber, and not at a fiber/air interface or other perturbation points to the fiber resulting in a more accurate representation of the optical mode-field distribution in the fiber. Since light is always in the fiber during the determination, no complicated fiber preparation steps or procedures are required and the mode-field distribution is determined as an average distribution along the length of the fiber under test.

Techniques are disclosed for aligning an optical transmitter with an optical receiver for a line-of-sight communications link, wherein the optical transmitter comprises a laser array emitter, the laser array emitter comprising a plurality of laser emitting regions, wherein each of a plurality of the laser emitting regions is configured to emit laser light in a different direction such that the laser array emitter is capable of emitting laser light in a plurality of different directions. The system can run produce emissions from different laser emitting regions until a laser emitting region that is in alignment with the optical receiver is found. This aligned laser emitting region can then be selected for use to optically communicate data from the optical transmitter to the optical receiver.

A hybrid automated testing equipment (ATE) system can simultaneously test electrical and optical components of a device under test, such as an optical transceiver. The device under test can be a multilane optical transceiver that transmits different channels of data on different lanes. The hybrid ATE system can include one or more light sources and optical switches in an optical test lane selector to selectively test and calibrate each optical and electrical components of each lane of the device under test.

A fiber diagnostics system facilitates testing, troubleshooting, tracking, identifying and logging information pertaining to fiber optic networks and their associated elements, including aggregated upstream and downstream statistics and trouble identification for all ports and services on the PON (Passive Optical Network), including Optical Line Networks and Optical Network Terminals (OLNs and ONTs). Traffic and network activities may be viewed as a whole or may be isolated to focus on specific networks, segments, WANs or LANs and individual client locations and devices, including devices residing on the customer premises beyond the point of demarcation.

A data communication network includes a plurality of network nodes coupled together via optical links and a network controller. Each network node includes a reflectometry analyzer that provides a characterization of physical properties of the optical links coupled to the associated network node. The characterization for each particular optical link provides a unique fingerprint of the physical properties of the particular optical link. The network controller determines a network path between a first network node and a second network node, wherein the network path traverses a first optical link, receives a first fingerprint for the first optical link from a first reflectometry analyzer, defines a signature for the path, the signature including the first fingerprint, receives a second fingerprint for the first optical link from the first reflectometry analyzer, the second fingerprint being different from the first fingerprint, and determines that the network path is not secure based upon the difference between the first fingerprint and the second fingerprint.

Techniques for tuning an optical communication system are disclosed. The system includes a first signal path for transmitting data, including an optical source, a first one or more variable optical attenuators (VOAs), a modulator, and a transmission fiber. The system further includes a second signal path for receiving data, including a receiver fiber and a second one more VOAs. The first one or more VOAs are tuned using the optical source in the first signal path for transmitting data, based on comparing a plurality of optical signal power values in the first path while a first tuning mode is enabled. The second one or more VOAs are tuned, using the optical source in the first signal path for transmitting data, based on comparing a plurality of optical signal power values in the second path while a second tuning mode is enabled.