A system for measuring a polarization extinction ratio (PER) using a reference master test jumper (MTJ) is disclosed. The system may include an optical source to transmit an optical signal via an optical fiber. The system may also include a device under test (DUT) communicatively coupled to the optical source via the optical fiber to receive the optical signal from the optical source. The system may also include an optical measurement component communicatively coupled to the device under test (DUT). In some examples, the optical fiber may be configured or initialized to be a reference master test jumper (MTJ) that minimizes inherent polarization extinction ratio (PER) of the optical fiber when measuring a polarization extinction ratio (PER) during a measurement action.

A digital processor (DP) is configured to obtain a temporal sequence of digital phase distortion measurements of a first optical signal received by a coherent optical receiver (COR) from an optical fiber link, where the first optical signal co-propagates with a second, power-modulated, optical signal in different frequency channels. The DP is configured to estimate a cross-correlation between the temporal sequence of digital measurements and a temporal sequence of powers of the second optical signal for a plurality of relative time shifts between the sequences, and to identify a location along the optical fiber link based on a magnitude of the cross-correlation exceeding a threshold for a particular time shift.

A system for measuring a polarization extinction ratio (PER) using a reference master test jumper (MTJ) is disclosed. The system may include an optical source to transmit an optical signal via an optical fiber. The system may also include a device under test (DUT) communicatively coupled to the optical source via the optical fiber to receive the optical signal from the optical source. The system may also include an optical measurement component communicatively coupled to the device under test (DUT). In some examples, the optical fiber may be configured or initialized to be a reference master test jumper (MTJ) that minimizes inherent polarization extinction ratio (PER) of the optical fiber when measuring a polarization extinction ratio (PER) during a measurement action.

A monitorable hollow core (HC) optical fiber comprises one or more hollow core anti-resonant fiber (HC-ARF) segments and one or more monitoring segments alternatingly connected with the HC-ARF segments, and where each monitoring segment comprises one or more non-HC-ARF constituents. A method for monitoring a monitorable HC optical fiber comprises transmitting one or more first optical signals on the monitorable HC optical fiber, detecting one or more second optical signals on the monitorable HC optical fiber, and monitoring one or more optical properties of the monitorable HC optical fiber using the first optical signals and the second optical signals, where the monitoring is enabled as a result of interactions between the first optical signals and the non-HC-ARF constituents of the monitoring segments.

A monitorable hollow core (HC) optical fiber comprises one or more hollow core anti-resonant fiber (HC-ARF) segments and one or more monitoring segments alternatingly connected with the HC-ARF segments, and where each monitoring segment comprises one or more non-HC-ARF constituents. A method for monitoring a monitorable HC optical fiber comprises transmitting one or more first optical signals on the monitorable HC optical fiber, detecting one or more second optical signals on the monitorable HC optical fiber, and monitoring one or more optical properties of the monitorable HC optical fiber using the first optical signals and the second optical signals, where the monitoring is enabled as a result of interactions between the first optical signals and the non-HC-ARF constituents of the monitoring segments.

A test instrument is operable to test optical components of a fiber optic network. The test instrument includes a laser having a back-facet monitor. The test instrument measures a performance parameter of an optical component being tested based on optical power of the laser measured by the back-facet monitor. The performance parameter is determined based on optical power measurements that account for drift of the laser.

An integrating sphere-equipped optical measurement device and optical connector polarity and type identification and loss measurement are provided. The optical measurement device includes at least two photodetectors that are optically responsive over different ranges of wavelengths. The optical measurement device receives one or more optical signals emanate from optical fibers of an optical fiber cable. The optical measurement device determines an optical intensity or loss of the one or more optical signals based on a measurement made by a corresponding photodetector whose responsivity range includes a wavelength of the one or more optical signals. The optical measurement device determines one or more respective positions where the one or more optical signals impinged on a sensor. The optical measurement device determines a polarity of the optical fiber cable based on both the one or more positions and one or more or transmitting positions of the one or more optical signals, respectively.

According to examples, a system for measuring polarization dependent loss (PDL) for a device-under-test (DUT) may include a tunable laser, a polarization element and a power meter. The tunable laser may emit an optical signal to sweep across an optical band at a constant rate. The polarization element may scramble polarizations states of the optical signal emitted from the tunable laser. The power meter may take power measurements associated with the optical signal emitted from the tunable laser, wherein the power measurements from the power meter are used to determine a maximum insertion loss (IL) and a minimum insertion loss (IL) associated with the device-under-test (DUT). An average insertion loss (IL) and a polarization dependent loss (PDL) for the device-under-test (DUT) may be calculated based on the maximum insertion loss (IL) and the minimum insertion loss (IL) associated with the device-under-test (DUT).

Methods and systems are disclosed for characterizing a polarization-dependent loss or gain (PDL/G) of an optical device under test (DUT), such as an optical fiber link, from an optical signal having passed through the optical DUT. The optical signal is substantially unpolarized upon entering the optical DUT. The method can include varying a state of polarization (SOP) of the optical signal over a plurality of sampled SOP conditions to produce a respective plurality of SOP-varied optical signals; performing a polarization-analysis and detection operation on the plurality of SOP-varied optical signals to acquire a respective plurality of detected signal sets, each detected signal set including at least one polarization-analyzed detected signal; and determining, as the PDL/G of the optical DUT, a polarization extinction ratio parameter representative of a ratio of maximum to minimum power levels measured among the polarization-analyzed detected signals of the plurality of detected signal sets.

An integrating sphere-equipped optical measurement device and optical connector polarity and type identification and loss measurement are provided. The optical measurement device includes at least two photodetectors that are optically responsive over different ranges of wavelengths. The optical measurement device receives one or more optical signals emanate from optical fibers of an optical fiber cable. The optical measurement device determines an optical intensity or loss of the one or more optical signals based on a measurement made by a corresponding photodetector whose responsivity range includes a wavelength of the one or more optical signals. The optical measurement device determines one or more respective positions where the one or more optical signals impinged on a sensor. The optical measurement device determines a polarity of the optical fiber cable based on both the one or more positions and one or more or transmitting positions of the one or more optical signals, respectively.