Viewpoint: Why collaboration on the ground is vital for LEO satellite constellations in the sky

He and his team are creating a collaborative platform of completely new smart universal chassis’ designs, where the modules and habitat communicate with one another, interacting intelligently and almost all elements are hot-swappable. This, he says, is vital as engineers are innovating against the clock to deliver what’s needed to ensure these new networks, thrust into the limelight by the likes of Elon Musk’s SpaceX and Jeff Bezos’ Amazon, can function and adapt to changing requirements.

LEO and new satellite infrastructure

The satellite industry is going through something of a renaissance, with new LEO constellations set to play an increasingly important role in the industry, and wider society for that matter, transporting and perhaps even processing large chunks of our data.

Increasing data demands, driven in part by the Internet of Things (IoT) and other IP-based applications, are providing new opportunities for satellite operators and those engineering the RF equipment required to build and operate these new networks.

Much smaller and lower cost than their larger medium Earth orbit (MEO) and geosynchronous (GEO) predecessors, LEO satellites will be mirrored on the ground by a larger network of smaller Earth stations.

A few hundred kilometers above earth’s surface, 36 times closer to the Earth than GEO satellites, and whizzing across the sky at several kilometres per second, there are new and very real challenges for those of us engineering for the ground segment. Not least how to handle the many handovers as one satellite exits line-of-sight and another enters.

RF equipment, frequency converters, amplifiers, switch matrices and RF over fibre technologies are already being re-engineered, ready for manufacture at a scale we’ve not seen up to this point in this industry; and at a cost we’ve not seen either. This all needs to happen without compromising on resilience, redundancy and the extremely high quality and reliability for which our small part of this industry has become synonymous.

This will be fundamental to enabling these new LEO constellations to achieve their promise; to connect billions more people and enterprises, become part of the incoming 5G infrastructure and open up much needed bandwidth for IoT applications, expected to grow significantly this decade.

According to McKinsey & Company, there are currently around 2,500 active satellites in orbit; but experts predict that within the next decade there could be as many as 50,000 new satellites launched. This may well be an overestimate, but if even 10 percent of this figure comes to fruition, twice as many new satellites will have been launched than are currently active in the entire sky.

This is providing a new challenge for engineers engaged now to design what’s needed to make these internet-from-space, high speed, low latency dreams a reality. The first products designed to meet these new requirements are already being shipped – but what are the main challenges and how are we meeting them head on?

Reengineering for a new era

LEO constellations will require multiple tracking antennas, or programmable flat panel antennas, with RF connections being routed intelligently to offer signal and equipment redundancy.

This will mean that within existing teleports new antenna arrays and new Master Control Rooms (MCRs) or Network Operating Centres (NOCs) will be needed to allow local or remote control. These centers will need to be interconnected, forming a web of control rooms distributed across the globe.

There’s a drive for more compact RF switch matrices to bring down the cost, but despite this they continue to need functionality for uplink, downlink or both. This is absolutely essential to ensure multiple LEO tracking antennas can be connected and switched by a master control system.

What we’re doing in response is creating a new standardised range that can do more, operates over wider Intermediate Frequency bandwidths to provide high speed, low latency services across the globe. As you might imagine, this is pushing boundaries in engineering.

Building for the future

For as long as our industry has existed the ground segment has flown under the radar; obscured by the shadow of the satellites we serve with their dramatic launches and orbital status.

Conventionally the Earth stations have, up until now, existed to collate and transfer RF signals to where they need to be delivered often referred to as “bend pipe systems” – with limited processing, storage or smart functionality. The future equipment will be intelligent, adaptable and agile in their characteristics.

This may now be changing though, as satellite begins to play a more important and digital role in the backbone of future 5G networks. In the future we know there will be a need for more data processing and are ensuring flexibility as we invent a new future-proofed design language that will span this period of change.

The low cost, high volume switch

As an industry within an industry, engineers in the ground segment are finding they need to adapt from designing relatively low quantity, extremely high quality RF equipment towards lower cost, larger scale but without compromising on the key characteristics of resilience, dependability and reliability.

We are standardising, introducing smart features and flexible modular designs to ensure our pillars of resilience and redundancy can translate into this new era for satellite. We have been working hard to condense our product range to fit a new chassis’, reduce existing module sizes down and at the same time maintain or improve RF performance.

We’ve already designed five chassis that will replace a large majority of all our current chassis variants – condensing 28 chassis types.

Any module, whether it be RF router, combiner, splitter, amplifier, LNB power or fibre should fit within a standard chassis, meaning it can be a standalone product, but the functionality must be greater than before too.

Whole product ranges are becoming modules, which can be hot-swapped in and out of these chassis’ in a matter of minutes, with multi-function mix and match modules in the same chassis resulting in the need for less rack units. At the end of life, modules can be renewed without the need to replace an entire unit. This is especially important where low cost units such as power supplies and fans can be easily replaced, becoming serviceable parts whilst the RF system modules remain operational and software upgradeable.

We see the need for the chassis themselves to also become much smarter, forming a habitat which tracks which modules are installed and records the operational history of the unit alongside other factors like heat, humidity, operational cycles and other important environmental and functional data.

The benefits for all of this are significant, including common spares provisioning, rack space saving and a robust habitat for all ETL products which can be configured to suit high resilience applications. In field upgrades are also much easier by, for example, adding LNB powering or a fibre interface to an existing product if it’s later required.

Collaboration and standardisation

We believe this is a blueprint for our industry; to make the leap to LEO possible and will be inviting partners and third party providers to work with us on this journey.

We can only achieve this forward step through greater standardisation and collaboration between space and ground, partners and friendly competitors alike.

Dr Esen Bayer, Chief Technology Officer at ETL Systems