Manufacturers of antennas for maritime satellite communications have increased power and radio frequency performance for higher levels of broadband on ships
Advances in antenna technology have led to greater power, seamless band switching and more efficient installation and commissioning. There are improvements in performance and antenna sizes and weights have fallen, opening more markets for higher bandwidth satellite communications for smaller vessels.
Although there have been improvements in L-band services, most of the recent advances in antenna technology have been focused on maritime VSAT, including Ku-band, high-throughput satellite technologies and Inmarsat’s Ka-band Global Xpress (GX).
Cobham Satcom introduced a high-power version of its Sailor 100 GX antenna in September to enable more data to be transmitted over Inmarsat’s Ka-band services to maritime users. This antenna’s reflector is 1 m in diameter and is stabilised on three axes.
Because of a high-power block up converter (BUC) on the electronics side of the antenna, Sailor 100 GX High Power delivers twice the radio frequency power of standard GX terminals. Cobham said this power boost comes from a military-grade 10-W amplifier, which significantly increases upload speeds and facilitates a more reliable link to the GX satellites in all conditions. This should ensure continuity in the flow of mission-critical data from ships and improve the overall experience of shipboard crew communications.
High-power GX terminals also improve the economics of pushing large amounts of data from ship to shore, said Inmarsat Maritime president Ronald Spithout. “With higher throughput hardware we can provide higher bandwidth to ships, offshore support vessels, passenger ships and superyachts,” he told Maritime Digitalisation & Communications during the SMM exhibition in Hamburg, Germany in September.
“We have seen growth in these markets this year with more installations on small cruise vessels and as offshore support vessels are brought out of layup.” This has been for Fleet Xpress (FX), the combination of GX and FleetBroadband L-band.
Another improvement in antenna installation has extended the number of terminals installed on offshore vessels. “We diversified FX with higher bandwidth and dual-antenna options,” said Mr Spithout. “Offshore vessels could be in the shadow of drilling rigs, platforms and superstructure of vessels that block satellite signals.”
This is why a Cobham Satcom dual-antenna package includes two GX antennas and one for FleetBroadband, achieved through a single GX modem unit using embedded intelligent software, which eliminates the need for costly terminal and network control devices in below-deck racks.
“We leveraged our antenna platform for new levels of performance and more bandwidth capabilities”
Cobham Satcom chief executive Janus Pagh said adding the 10-W BUC to the Sailor 100 GX antenna enables these antennas to be used on expedition and river cruise ships. “We leveraged our antenna platform for new levels of performance and more bandwidth capabilities,” he told MDC. “It means vessels can have high power without needing a large antenna.”
He also explained that a dual antenna package could include high power antennas with a simple installation and commissioning process. “We have a one-cable solution for dual antennas so there is no need for a mediator or arbitrator,” said Mr Pagh. It is a simple solution with less risk of failure, saving on the number of RF cables and below-deck equipment.
With less hardware in below-deck racks, Inmarsat has worked with satellite communications providers on network service devices that use software for managing FX coverage. These devices control seamless switching between Ka-band and FleetBroadband and allocate bandwidth for different applications.
This can include bandwidth for crew welfare, operations or for data transmissions, said Mr Spithout. “We continue to develop the software and hardware and have more applications on board ships for FX,” he said. “This includes application-triggered bandwidth, dynamic allocated bandwidth and applications for service providers.”
Network service devices allocate bandwidth to service providers without sacrificing bandwidth used for crew communications and operations applications. Voice services also have their own dedicated lines on FX “so it does not eat into other bandwidth and can be monitored better” said Mr Spithout.
Cobham Satcom also provides antennas under the Sailor brand for Ku-band VSAT. It made an inroad into the Chinese Ku-band VSAT market in August when it announced a contract to supply Sailor 900 VSAT to 16 dredging vessels. This order from China Communications Construction Co (CCCC) Dredging came through Cobham Satcom's distribution partner, Beijing Highlander Digital Technology.
In this contract, Sailor 900 VSAT will replace existing FleetBroadband hardware on 16 vessels over 24 months, with an option to deploy these on a further six vessels.
Sailor 900 VSAT antennas come factory-tested, balanced and ready for onboard commissioning. There is just one cable between the antenna and below-deck equipment, which saves time during installation and commissioning. These antennas have been tested to work with high-throughput satellites, such as those operated by Intelsat in its EpicNG constellation, and are prepared for conversion from Ku-band to Ka-band Inmarsat FX.
Some VSAT hardware is able to switch between bands of radio frequency without any interaction from crew. These multi-band antennas are available from suppliers such as Cobham Satcom, Intellian and KVH Industries.
Intellian vice president for global satellite communications Jon Harrison said VSAT antennas are designed for switching between Ku-, Ka- and C-bands and for multiple satellite orbits. For example, antennas supplied to Carnival cruise ships can manage signals from geostationary Ku- and C-band satellites and Ka-band from SES’ medium Earth orbit (MEO) O3B satellite constellation.
“We have taken this experience into our NX range of antennas so they can leverage MEO and other constellations in the future,” said Mr Harrison.
Intellian introduced an 85-cm diameter maritime VSAT antenna that can be converted from Ku-band and Ka-band by replacing the RF assembly and feed. The v85NX antenna supports geostationary constellations and will be compatible with future low-Earth and MEO satellites, including wide Ka-band networks.
There are different BUC power options up to 25 W for this 85-cm antenna. It has dynamic motor braking and its power, transmit and receive signals are integrated in one coaxial cable for simplified installation. The antenna is controlled using the AptusNX software that has alerts and diagnostic capabilities.
Intellian also developed a high-power antenna for Inmarsat GX. The GX100HP has a 10-W BUC that enables upload speeds of 5 Mbps and more than 10 Mbps download capabilities on Fleet Xpress. It can also be used in dual-antenna packages and there is a kit for converting existing v100 antennas into this high-power GX unit.
“Vessel owners can get 10 Mbps download and 3 Mbps upload with a 60-cm antenna on the HTS coverage”
KVH’s TracPhone VSAT hardware includes a 1.1-m diameter V11 antenna that operates on both C-band and Ku-band. Another KVH antenna is the TracPhone V7 with a 60-cm reflector. They operate on KVH’s mini-VSAT Broadband service and are capable of connecting to widebeam Ku-band and spot beams of high intensity Ku-band on Intelsat EpicNG. “Vessel owners can get 10 Mbps download and 3 Mbps upload with a 60-cm antenna on the HTS coverage,” said KVH co-founder and chief executive Martin Kits van Heyningen
KNS offers Z8 MK3 Allinone as an integrated and portable VSAT for maritime applications. This includes a Ku-band antenna, modem and control unit within the radome. This contrasts with conventional VSAT, which has a fixed antenna on deck and the other components in a below-deck rack.
Z8 MK3 Allinone is based on KNS's SuperTrack Z-Series MK3 body structure and the antenna has an 83-cm diameter reflector. There are only two cable connections for power and the ship’s own communications network. Z8 MK3 Allinone was designed for easy maintenance as service engineers can uncover the radome to inspect all compartments of the system. There is also a hatch below the VSAT unit for access.
This VSAT is supported on a tripod with lifting magnets for stability when the position is set and can be moved by an engineer to different areas of a vessel when required.
Hyundai Heavy Industry is deploying Z8 MK3 Allinone VSAT on its newbuildings for KNS to field test them at sea. This portable unit could be used for testing RF performance around a ship during final commissioning phases to identify an optimum position for the antenna.
Telenor Satellite expanded the types of antennas that can be used over its regional Ka-band maritime VSAT by approving one from Germany-based EPAK, enabling the DSi9 antenna to operate on Thor 7’s mobility service.
This approval process evaluated how the terminal can be accurately aligned to the satellite from a moving ship. If the pointing is off by more than 0.2˚, the connection fails and the transmission to the satellite must be halted to prevent interference with other signals. EPAK antennas were also successfully tested for automatic beam switch, robustness and ease of handling.
Thor 7 provides broadband connectivity over the main European shipping lanes and utilises high-powered spot beams for maritime, passenger shipping and offshore applications. The DSi9 antenna weighs 58 kg and comes with a 90-cm antenna. Trials have demonstrated that around 5-6 Mbps of bandwidth can be achieved through these antennas.
Telenor Satellite director of datacoms Jan Hetland said the BUC is a key component of an antenna and can be configured for higher bandwidth. “We have done trials with different platforms and can go to 15 Mbps upload speeds depending on the BUC configuration,” he said.
“We see a change because of smaller antennas and lower prices that are opening these lower-end markets”
These rates have come from using VSAT on passenger ships operating between Norway and Denmark and in the Mediterranean. Thor 7 is also being used on fishing vessels where a 60-cm diameter antenna can be installed to provide bandwidth of around 1 Mbps.
“We sell through our network of resellers to fishing markets in Norway, the UK and Ireland and have made inroads into the Spanish fishing fleet,” said Mr Hetland. “They have lighter 60-cm antenna for VSAT on smaller vessels.”
He predicts that workboats and tugs will be the next segment to install VSAT. “We see a change because of smaller antennas and lower prices that are opening these lower-end markets,” he said.
Terminals have been developed for Iridium Certus L-band which is being tested this year before the full commercial launch of this low Earth orbit Next constellation.
Thales developed a terminal for Iridium Certus that is incorporated in its Vesselink service. This offers global pole-to-pole satellite coverage for maritime communications with a robust network for reliable voice, text and web communications for seafarers.
This antenna weighs 3.4 kg for quick installation and integration into existing vessels or new fleets. It has three dedicated voice over IP channels, bandwidth of 700 kbps up and 352 kbps down for data and location tracking. Vesselink is open for onboard applications, such as telemedicine, cargo monitoring, real-time weather information and at-sea reporting.
Thales’ antenna has an embedded wifi access point and can connect up to 12 devices. Vesselink has enabled functionality for Android and Apple devices and administrative control for captains and fleet managers to manage connectivity efficiency and costs.
Cobham Satcom sent its first terminal for Iridium Certus to a vessel for testing in August. Sailor 4300 L-band is designed to serve as a primary solution or as a VSAT-companion. The terminal will provide multiple high-definition voice lines, alongside IP data speeds starting at 352 kbps.
These speeds could be increased to 704 kbps in future through a firmware update once the complete constellation is commissioned. Cobham Satcom integrated the Iridium broadband core transceiver module into the antenna of the terminal for more flexible placement, lower installation costs and optimised link performance. Lars Thrane is also working with Iridium to develop terminals.