Submarine Cable Technology Research Articles

SMART submarine cable technology can facilitate acoustics on the global scale

The submarine cable industry is beginning to share their infrastructure for ocean observing. Science Monitoring And Reliable Telecommunications (SMART) Subsea Cables is working to integrate temperature, pressure, and seismic acceleration sensors into commercial cables (∼70 km spacing) to support climate monitoring and disaster risk reduction on the global scale. The seismic and pressure sensors are expected to have sensitivity at low acoustic frequencies, (e.g., <50 Hz and <5 Hz, respectively); future systems could include hydrophones and other sensors. Further, telecom rated branching cables supporting multipurpose “nodes” are becoming a reality (per existing dedicated science cable systems). These can support low frequency transceivers and autonomous undersea vehicles (AUVs). With cabled power, these would be part of the fixed/mobile acoustic tomography system measuring ocean heat content and more generally for transporting energy, data, and acquiring multidisciplinary data throughout a large volume of the ocean. A 3700 km SMART ring system in Portugal will be ready in 2026 and one connecting Vanuatu and New Caledonia is starting. Others in planning stages that could include these concepts are: Far North Fiber connecting Norway/Finland/Ireland with Japan, the NSF proposed SMART cable connecting New Zealand with Antarctica, New Zealand-Chatham Islands, and Lisbon-Egypt through the Mediterranean.

New developments in submarine cable technology can facilitate acoustics in Polar regions and on the global scale

The subsea telecommunications cable industry is expanding their present single purpose infrastructure to include ocean observing capability. Science Monitoring And Reliable Telecommunications (SMART) Subsea Cables is working to integrate temperature, pressure, and seismic acceleration sensors into commercial cables (∼70 km spacing) to support climate and ocean observation, sea level monitoring, and tsunami and earthquake early warning on the global scale. Furthermore, telecom rated branching cables with power feed units supporting multipurpose “nodes” are becoming a reality. Acoustic capability can be integral to both. Major uses of these nodes include supporting low frequency transceivers enabling basin scale tomography and geo-positioning of mobile assets and docking for autonomous undersea vehicles (AUVs). Enabled by cabled power, these would be part of the fixed/mobile acoustic tomography system measuring ocean heat content at the speed of sound and more generally for transporting energy, data, and acquiring multidisciplinary data throughout a large volume of the ocean. Both variants and hybrids between can support the necessary acoustics contribution to ocean observing. Two proposed systems can support polar applications: Far North Fiber Express connecting Norway/Finland/Ireland with Japan via the Canadian Northwest Passage, and the NSF proposed SMART cable connecting New Zealand with McMurdo Base, Antarctica.

Technical and economic demands of HVDC submarine cable technology for Global Energy Interconnection

Power transmission across the sea is an important part of global energy interconnection (GEI). To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind power development, this study a) analyzes the requirements of the GEI backbone network pertaining to direct current (DC) submarine cable technology, and b) defines the key technical and economic indices of ultrahigh-voltage direct current (UHVDC) submarine cable based on theoretical computations. The research is based on the thermoelectric coupling model and the finite element method. It is shown that the dielectric strength of the insulating materials of the ±800 kV~±1100 kV/ 4000 MW~12000 MW UHVDC submarine cable (extrusion insulation) should be not less than 43~65 kV/mm, while the heat resistance is not less than 110 °C. As the cost of submarine cable is 5~10 times higher than that of the overhead line, the project investment need to be decreased to a level within the economical carrying capacity to guarantee extensive applicability of the HVDC submarine cable technology.

Study on AC Resistance of Layering Enamelled Stranded Conductor

In recent years, with the rapid development of large-length ultra-high-pressure voltage extrusion insulated submarine cable technology, the cable system in the medium-length offshore power grid interconnection project has been gradually replaced by XLPE insulation by traditional oil-paper insulation. There are many large cross-section conductors used in long-distance power transmission cables, and according to the IEC 60287-1-1, it is recommended to use Milliken conductors to reduce the AC resistance of conductors, at the same time, in submarine cables, there is a high requirement on the water-blocking performance of conductors and the water resistance of Milliken conductors is poor, so it is not used in submarine cable conductors. This paper puts forward a layering enamelled stranded conductor and a calculation method of AC / DC resistance ratio for it. The validity of the calculation method is verified by experimental tests. At the same time, the calculation shows that the AC / DC resistance of the conductor at 1800 mm2 nominal cross section can be reduced by 16% compared with the conventional round compacted conductor in the prior art. The effectiveness of this conductor in reducing AC resistance is verified by finite element simulation.

Liberte! Egalite! Telegraphie! The French Cable Station in Orleans, Massachusetts

Sometimes factors-such as government regulations, personal preferences, or even national pride-can intervene to preserve an outmoded technology long after technical considerations would dictate its demise. The town of Orleans, nestled in the elbow of Cape Cod, Massachusetts, harbors one such product of benign neglect: the French Cable Station Museum. This article describes the history of the telegraph-cable connections between France and the Cape, dating back to 1879, only thirteen years after the first permanently successful transatlantic cable was laid. French patriotism influenced the routing and operation of the cables as much as economics or engineering. The submarine telegraph cable was an interesting propagation medium in its own right. Even after intercontinental radio communications became practical, some of the best minds in the communications industry applied themselves to the problem of maximizing cable-transmission rates, with mixed results. I review two significant technical advances in submarine-cable technology that occurred between 1900 and 1930. Finally, I conduct an armchair tour of the French Cable Station Museum as it is today, one of the few communications museums in the country which preserves historic operating equipment at its original site.

Submarine cables and protections provided by the law of the sea

This article describes the evolution and significance of submarine cable technology. It reviews the causes of cable failures due to man-made ‘external aggression’ and the industry's response. Though sophisticated cable protection methods have been developed, threats continue as fishing technologies and locations evolve. The article identifies the need for adequate ocean policies to supplement existing corporate strategies. The author concludes that the degree of protection afforded to submarine cables would be improved if parties to the UN Convention on the Law of the Sea were to adopt domestic legislation to implement the cable-protection provisions of the Convention.

Girdle round the earth

Puck, in a Shakespearean comedy set in Athens, boasted: ‘I'll put a girdle round the earth in forty minutes’. His claim was never realised, but today—thanks to submarine cable technology—the human voice can make this long journey in a tenth of a second. This article reviews the present state of submarine cable technology; its relationship to communication by satellite; and the implications of optical fibre systems.

Digital Transmission over Submarine Cables

The problems of transoceanic transmission of large volumes of information have been raised increasingly over the past few years. Lately, the need for transoceanic digital communications has been of interest. This paper discusses the significance of these trends and examines the technical prospects for handling large volumes of digital traffic using submarine cables. Concentrating on transatlantic traffic, an argument is built up for an all-digital cable by the year 1970. Submarine cable technology is reviewed briefly and several approaches to transoceanic digital transmission are discussed, using known and estimated cable technology. A final approach is described in detail using existing repeater and cable technology for the transmission of multilevel digital data at rates in excess of 1.5 mb/s.