SEPTEMBER 2023 | technology report | Space systems
With the increasing risk of disruption – whether cyber, EW or even kinetic – to the satellite constellations relied on by armed forces for communications and connectivity, what steps are industry taking to create more resilient and flexible networks?
Above: Traditional geostationary satellites used for military communications are being supplemented by sophisticated multi-orbit networks to better protect against disruption. (Image: Thales Alenia Space)
Armed forces and security agencies around the world are demanding even more secure and resilient levels of connectivity to support an increasing range of use cases today and in the future.
Military satellite communications or MILSATCOM already play a critical part in supporting the day-to-day operations of armed forces, particularly when it comes to intelligence-gathering, crisis response, maritime surveillance, peacekeeping and humanitarian aid and disaster relief.
Traditionally, MILSATCOM has been enabled by deployment of small numbers of large, exquisite and expensive satellites operating in geostationary Earth orbit (GEO), some 35,000km above the Equator.
This GEO-based MILSATCOM was heavily relied upon by coalition forces operating in the Middle East and South Central Asia in the first two decades of this century, where it was used as a primary means of communication in almost every operating environment.
Today, the threat has changed and armed forces must ensure their communications networks are protected from highly capable peer and near-peer adversaries with the capability to degrade, disrupt and in some cases, even destroy MILSATCOM components on the ground, at sea and in space.
Threats include cyber and electronic warfare effects as well as anti-satellite (ASAT) missiles launched from Earth and tasked with the destruction of a satellite in GEO – an attack which could lead to significant loss of coverage around the world for an armed force.
In response, government and industry are increasing levels of security and resilience in MILSATCOM using a number of approaches. These include the creation of multi-orbit networks which integrate satellite constellations in GEO, medium Earth orbit (MEO) and low Earth orbit (LEO).
LEO-based SATCOM – developed in many cases as a commercial solution – is one of the latest capabilities being adopted although its application has yet to be fully exploited.
NATO in space
LEO is of particular interest to NATO which is considering using the technology to support its Space Policy.
According to this doctrine, NATO is demanding increased levels of ‘security and resiliency’ as well as optimisation of tactical through strategic communications across the Arctic and High North.
But the policy also highlights concerns regarding the proliferation of LEO constellations which is contributing to an ‘increasingly crowded spectrum’ in terms of space-based connectivity.
Speaking to Shephard, an official from the NATO Communications and Information Agency (NCIA) discussed how LEO satellite constellations are ‘dramatically increasing in [terms of] SATCOM due to their advantages compared to geostationary ones’.
‘NATO has used LEO services for a long time in different flavours [and] the NCIA has been following the developments in LEO technologies closely. We are currently investigating potential use of advanced capabilities in LEO SATCOM, such as lower latency, higher data rates, wider coverage or smaller terminals,’ the official said.
As it continues to explore its Space Policy, NATO is working on capability development and subsequent military requirements statements featuring LEO SATCOM – strategies which remain under development by the alliance’s bi-strategic commands.
Expected completion of its space connectivity strategy is scheduled within the next ‘several’ years, the NCIA official confirmed to Shephard.
In May, the NCIA observed a multi-orbit demonstration conducted by LEO satellite constellation operator OneWeb and GEO satellite constellation operator, Eutelsat. Both companies are set to merge following a shareholder vote schedule for 28 September 2023.
According to a OneWeb official, the demonstration allowed NCIA officials to ‘get a real feel for the steps that both companies are making to provide a multi-orbit architecture that will deliver robust and resilient connectivity to deliver data and communications’.
At the event, Eutelsat highlighted its ‘Secure, Agile, Resilient and Assured (SARA) SATCOM for NATO’ concept, which comprises a ‘layered, multi-orbit communications plan providing end users with primary, alternate, contingency and emergency (PACE) connectivity should any specific network become disrupted or unavailable for any reason’.
OneWeb also showcased its 648-strong constellation of LEO satellites which offers military customers global coverage as well as communications on-the-pause and soon, on-the-move.
OneWeb’s network proved data throughput rates of up to 195Mbps during the NCIA demonstration in addition to latency levels as low as 70ms, OneWeb’s official confirmed to Shephard. Kymeta’s Hawk u8 flat panel user terminal, which was attached to the roof of a 4x4 Land Rover Discovery, was used to connect laptops and devices to LEO satellites overhead.
Above: Compact vehicle-mounted terminals and antennas can be used to hook up to LEO constellations to provide resilient communications on-the-move. (Photo: Kymeta)
Speaking after the event, Serge Cholley, head of defence and security at Eutelsat, described how these services would be suited to supporting armed forces operating in a multi-domain user environment.
‘SATCOM services that can operate in multiple orbits, [such as] GEO and LEO as well as exploiting multiple frequency bands, can better guarantees that communication links are available when required in challenging operational environments.
‘The opportunity that Eutelsat took to demonstrate this capability to the NCIA decision-makers came at a key moment for NCIA and NATO when the role of commercial SATCOM in a military environment is developing very rapidly,’ he added.
Also present at the event was OneWeb’s director of government, Charlie Clark, who explained how NATO is ‘interested in evolving beyond large, long-term and static communications infrastructure towards more agile, mobile and platform-based connectivity solutions for faster operational tempo.
'This really reflects the changing concepts of operation for NATO, moving away from big, static deployments to being much more agile. It’s going to take time to introduce that modus operandi but that’s the vision,’ Clark concluded.
Elsewhere, L3Harris Technologies is also pursuing a strategy to encourage greater take-up of multi-orbit solutions with the company’s general manager for SATCOM programmes, Jerry Adams, explaining to Shephard how such a concept promises to offer military customers ‘true resilience’ in terms of their connectivity.
‘Resiliency is a broad term for a number of methods to either protect communication over the air or make it difficult to locate a user of communications equipment. There are multiple methods of resiliency available to armed forces today, featuring dozens of categories and methods,’ he said before specifically highlighting multi-orbit diversity when it comes to the support of MILSATCOM.
‘Our near-peer adversaries are using more sophisticated electronic warfare technologies and employing advanced techniques that aim to prevent a warfighter’s connectivity, in addition to attempting to locate, exploit and intercept the warfighter and their communications. This is a significant priority in the market,’ Adams noted.
Above: LEO constellations contain much larger numbers of satellites, providing multiple backup options in the event of hostile disruption. (Image: OneWeb)
‘We employ multiple techniques to offer resilience over our SATCOM terminals via protected waveforms, multi-orbit and multi-path diversity, as well as many other technologies to ensure secure and interoperable communications beyond line of sight,’ he continued.
‘Most SATCOM offerings today are in GEO but we are bringing in products and capabilities that provide MEO and LEO connectivity,’ Adams added. He highlighted L3Harris’s Multi-Constellation Modem (MCM)-500 product which, according to company literature, is a ruggedised, ground mobile SATCOM modem capable of supporting high data throughput for two simultaneous connections to LEO, MEO and GEO constellations.
Essentially, the MCM-500 brings together multiple SATCOM models into a single housing which can be carried as a soldier-portable system or as vehicle-mounted solution for communications on-the-move.
The MCM-500 has been optimised to exploit commercial space-based constellations, particularly LEO networks which continue to proliferate. Examples include: Iridium, OneWeb’s Global Connectivity Platform; Amazon’s Project Kuiper; and Space X’s Starlink.
Strength in numbers
Beyond offering an alternative to GEO and MEO satellite, connectivity, LEO constellations are also designed to be resilient to disruption due to their sheer numbers.
Unlike more traditional GEO solutions, LEO constellations can encompass dozens, hundreds or even thousands of satellites around the world, so should a small number become degraded, disrupted or destroyed, the network can self-heal and continue providing uninterrupted service to end users.
OneWeb LEO satellites, which are manufactured by Airbus, operate in a total of 12 planes, performing a ‘Venetian blind’ style hand-off between one another as they pass overhead.
‘Imagine each beam as a rectangular cell, each measuring 1,600km by 1,600km and backed by more than 40 Satellite Network Portals (SNPs) globally. Handover between satellites can be measured in tenths of milliseconds, with approximately 2.5 minutes between each satellite,’ OneWeb’s Clark explained.
Additional benefits of LEO-based MILSATCOM include greater connectivity in the Arctic Circle and High North – the area north of the 50th Parallel and a particularly relevant area of operation for NATO and its partners.
Historically, end users operating in the Arctic Circle have had to improvise to connect to GEO constellations due to their position over the Equator. As an official from the European Space Agency explained: ‘Even when a link can be made, it can be prone to interruption from icing on antennas or from disruption caused by heavy seas’.
The future operating environment will be a complex one for armed forces around the world. But multi-orbit diversity, aggregated with other line of sight and beyond line of sight solutions such as mobile ad hoc networks (MANETs), will provide increased security and resilience for end users globally, no matter what mission set they are undertaking.