Aspects of the present disclosure describe a three-way branching unit switch module having a small footprint suitable for application in an undersea application.

An improved deepwater optical fiber cable with abrasion protection and techniques for manufacturing the same are provided. For example, the abrasion protected deepwater cable may be a modification or enhancement of an existing special application (SPA) optical fiber cable. One or more additional layers of metallic tape and jackets may be added to the outermost layer of the SPA cable. The tape and jacket layers may have different thicknesses and may be made from different materials to optimize protection against man-made objects or otherwise naturally occurring materials in deep water environments, such as fish aggregation devices (FADs).

Production process of a submarine optical amplifier (99) for optical telecommunication systems, and relative submarine optical amplifier (99), comprising: covering at least a central body (3) for making a central portion (6) of a layer of electrically insulating material (60) which covers a vessel (50); inserting an apparatus for optical amplification (5) at least partially in an housing cavity (4) of the vessel (50); assembling the vessel (50) by fixing at least a first end body (1) to the central body (3) for closing said housing cavity (4); completing the electrically insulating material (60) by at least partially covering the first end body (1) with the electrically insulating material for making a first portion (6′) of the layer of electrically insulating material (60), wherein a first thermally insulating element (7) is interposed between the central body (3) and the first portion (6′) of the layer of electrically insulating material (60).

Cables having buffer elements formed with two-dimensional fillers are described. A cable may include at least one optical fiber, and a buffer element may be formed around the at least one optical fiber. The buffer element may be formed from a material that includes a polypropylene-containing polymeric resin, a filler added to the polymeric resin that includes a plurality of two-dimensional particles, and an amphiphilic compatabilizer. A jacket may be formed around the at least one optical fiber and the buffer element.

In an optical network having a terrestrial terminal and an open cable interface (OCI) connecting a submarine cable to a terrestrial cable, the OCI may include a filter positioned on an optical path between the terrestrial cable and the submarine cable and configured to pass first communication signals of a first frequency band, and filter out secondary signals of a second frequency band that does not overlap with the first frequency band. The secondary signals may be looped back to the terrestrial terminal. The terrestrial terminal may detect the looped back secondary signals, and in response, determine the presence of the OCI and that the supervisory signals were rerouted by the OCI.

Rectangular equidistant projection is applied to coordinates for path fragments of a plurality of fiber optic routes. A bounding box is generated for each path fragment. For each cell of a grid of cells where its bounding box overlaps with a bounding box created by the cell, each path fragment is placed into the cell of the global grid. For any cell with more than one path fragment, each path fragment inside the cell is compared to every other path fragment in that cell. For any path fragment with overlapping bounding boxes, the length of the overlap is saved. A table of cumulative overlap distances between path fragments is generated to identify overlapping segments and cumulative lengths of the overlap distances.

In an optical network having a terrestrial terminal and an open cable interface (OCI) connecting a submarine cable to a terrestrial cable, the OCI may include a filter positioned on an optical path between the terrestrial cable and the submarine cable and configured to pass first communication signals of a first frequency band, and filter out secondary signals of a second frequency band that does not overlap with the first frequency band. The secondary signals may be looped back to the terrestrial terminal. The terrestrial terminal may detect the looped back secondary signals, and in response, determine the presence of the OCI and that the supervisory signals were rerouted by the OCI.

The invention discloses an underwater umbilical cable which is capable of temperature and vibration measuring and three-dimensional shape reconstruction, wherein underwater umbilical cable is used to connect underwater equipment and aquatic equipment; the underwater umbilical cable comprises an outer sheath, armored steel wires, an inner sheath, a power cable, a communication optical cable, a steel pipe, three strain measuring optical fibers, three temperature measuring optical fibers, a distributed optical fiber strain interrogator, a distributed optical fiber temperature interrogator and a processor. The invention can collect the operation status data of the umbilical cable for a long time. The collected data is highly objective, can truly reflect the real-time operation status of the umbilical cables, and plays an important role in guaranteeing the long-term submarine oil and gas exploitation.

An assembly assembled by a plurality of sections put together, wherein the section includes

an elongated structure having a left end and a right end,

an optical fiber having a left end and a right end and extending from its left end to its right end so that:

the left ends of the elongated structure and of the optical fiber are located on the same left side of the section, and

the right ends of the elongated structure and of the optical fiber are located on the same right side of the section,

each end of the optical fiber is enclosed in a junction box, the box of the right or left end of the optical fiber of the section being assembled with the junction box of the left end or right end of the optical fiber of another similar section to optically connect the optical fibers of two sections.

In an aspect of the present disclosure, a submarine device includes a main tail cable connected to a submarine cable, a first branch tail cable including a first group of optical fibers among a plurality of optical fibers included in the main tail cable, a second branch tail cable including a second group of optical fibers among the plurality of optical fibers, a branch member that couples the main tail cable to the first and second branch tail cables and including therein a through hole for branching the plurality of optical fibers included in the main tail cable into the first group and the second group, and a device main body including a first introduction part for introducing the first branch tail cable into the device main body and a second introduction part for introducing the second branch tail cable into the device main body.