An electromagnetic channel emulator system is disclosed. The system includes an electromagnetic switch matrix sub-system communicatively coupled to one or more systems under test and one or more simulation control layers. The system may include a high performance computing layer including one or more processing element nodes. The electromagnetic switch matrix sub-system may include one or more electromagnetic systems under test input/output layers and one or more high performance computing input/output layers. The one or more input/output layers may include one or more signal converters. The electromagnetic switch matrix sub-system may include one or more switches communicatively coupled to the one or more input/output layers and the high performance computing layer. The one or more switches may be configured to selectively position the one or more analog signals based on the received one or more simulation control layer signals.

A wavelength cross-connect device (20A) performs relay processing, the relay processing being such that wavelength multiplexed signal lights (1a to 1m), which are multiband transmitted from a plurality of routes M(1), are demultiplexed into different wavelength bands (S band, C band, and L band), and for each route, respective optical signals of the different wavelength bands (S band, C band, and L band) are amplified, then subject to rout change by WSSs and outputted to output side routes M(2). The device includes C-band WXC units 22 that are the same in total number as the wavelength bands of the optical signals of the respective wavelength bands and perform relay processing on optical signals of a specific wavelength band (C band) of the different wavelength bands. The device includes input side conversion units (31,32) provided on the input side of the C-band WXC units 22 for converting optical signals of wavelength bands other than the specific wavelength band into optical signals of the specific wavelength band. The device includes output side conversion units (35,36) provided on the output side for converting the optical signals of the specific wavelength band converted on the input side into the before-conversion optical signal. It is configured that the optical signals of the specific wavelength band directly input from the input side are directly output after the relay processing by the C-band WXC units.

A method includes determining a first power level by performing a first series of measurements based on a first series of burst transmissions from an optical transmitter of an optical network unit (ONU) in an optical network. Bursts in the first series of burst transmissions include a first modified preamble. A second power level is determined by performing a second series of measurements based on a second series of optical burst transmissions. Bursts in the second series of burst transmissions include a second modified preamble. A first power level (Po) and a second power level (P.sub.1) are determined based on the first power level and the second power level and one or more additional parameters associated with transmissions from the optical transmitter are determined based on P.sub.0 and P.sub.1. Based on the additional parameters, it is determined whether the optical transmitter complies with specifications of the optical network.

This application describes techniques for testing fiber optic telecommunication systems, such as undersea fiber optic cable systems. Testing terminals may be deployed at a location of terminating equipment for a fiber optic cable. The testing terminals may be operated remotely. The testing terminals may be configured to programmatically test the cable by loading one or more tests and automatically configure the cable's transmitters and receivers based on predetermined loading schemes selected based on the tests to be performed. The testing terminals may iterate over channels and fiber pairs of the cable and may use back-to-back tests to remove artifacts from test results. Using the described techniques, a cable's channels and fiber pairs can be fully characterized in the amount of time afforded for a typical testing schedule, which was not generally possible using conventional testing.

It is possible to allow a user to easily distinguish between an event at a place to be resolved and an event at a place having no problem on a path of a PON communication network to be measured. A light intensity distribution of return light is processed in a time-series order to detect an event at each position on a network. A parameter N1 relating to the total number of splitters present on a path of the network is specified, the number N2 of detections of the total number of splitters detected as an event is recognized, and in a case where “N1>N2”, a last detected event is associated with one optical splitter and is further displayed as an “uncertain splitter” in distinction from a normal splitter.

Disclosed are an apparatus and testing methods for performing testing operations over multiple types of links and through multiple potential points of failure to segment sources of problems, which may relate to reported or actual instances of service disruption in a network communication environment. The apparatus may perform service layer testing directly via an optical link, in addition to via Ethernet service layer testing. The apparatus may further conduct tests on other layers as well, including the physical layer, the network layer, and the link layer. To facilitate efficient testing, the apparatus may integrate programmable workflow profiles that specify tests to be conducted, and may interface with a cloud platform for sharing results of the tests, providing end-to-end testing of various components and types of links (whether optical or electrical, including wired and wireless links). Results of the tests may provide guidance to resolve detected problems.

Techniques for identifying sources of degradations within a PON include detecting that an optical profile of a segment of the PON is outside of a designated operating range, and comparing the drift over time of the segment's optical profile with respective drifts over time of optical profiles of other PON segments, each of which shares an OLT or a last mile termination unit with the segment as a common endpoint. Each segment's optical profile corresponds to characteristics of optical signals delivered over the segment (e.g., attenuation, changes in frequencies, changes in power outputs, etc.). The differences between the segments' drift(s) over time are utilized to determine the source of a degradation within the PON, and may be utilized to identify a particular component of the segment (e.g., the OLT, the last mile termination unit, or an optical fiber included in the segment) as being the source of the degradation.

Systems and methods include, responsive for a requirement to calibrate a single span in a multi-span optical line system where the single span includes a from-end node and a to-end node, determining no other upstream node in the multi-span optical multiplex section is currently calibrating or faulted; responsive to no other upstream node currently calibrating or faulted, calibrating the from-end node with a new target launch power into a fiber associated with the single span; and calibrating the to-end node keeping target launch power into a fiber associated with an immediate downstream span from the single span uninterrupted from a previous calibration. The to-end node and the from-end node are each (1) an intermediate line amplifier or (2) a terminal node and an intermediate line amplifier, in the multi-span optical line system.

Disclosed are apparatuses and testing methods for emulating an Optical Network Terminal (ONT) device for communicating or otherwise working with an Optical Line Terminal (OLT) device that was configured to operate with the ONT device. Such emulation may include configuring various settings of the apparatus so that the apparatus may appear to the OLT to be the ONT device. For example, the emulation may include accessing and using authentication/authorization related settings and network configuration settings of the ONT, thus permitting the apparatus to connect to a Passive Optical Network and test services and the quality of service experience without having to reconfigure the OLT.

Disclosed are apparatuses and testing methods for emulating an Optical Network Terminal (ONT) device for communicating or otherwise working with an Optical Line Terminal (OLT) device that was configured to operate with the ONT device. Such emulation may include configuring various settings of the apparatus so that the apparatus may appear to the OLT to be the ONT device. For example, the emulation may include accessing and using authentication/authorization related settings and network configuration settings of the ONT, thus permitting the apparatus to connect to a Passive Optical Network and test services and the quality of service experience without having to reconfigure the OLT.