Meeting the multi-orbit challenge on the ground
There’s a much broader role on the horizon for the satellite industry, and we are just at the beginning. The evolution of the satellite sector has seen an exponential rise of multi-orbit capabilities, a hugely attractive proposition that plugs the sector directly into the telecommunications infrastructure with the ability to bridge gaps in existing terrestrial connectivity and to deliver the best method of communication for the application at hand.
By Geoff Smith, Head of Sales, Space Comm Systems
According to analyst firm DataIntelo, the multi-orbit connectivity platform market was valued at $5.6 billion in 2025 and is projected to reach $25.8 billion by 2034, expanding at a compound annual growth rate of 18.5 percent - a huge leap. This forecast includes highly elliptical, low, medium and geostationary orbits and the combined ground infrastructure, including ground stations, software platforms and managed services.
This huge number reflects not only the arrival of Starlink, Amazon LEO, Telesat Lightspeed, and many others, but also a move from legacy GEO operators such as SES and Eutelsat to embrace hybrid multi-orbit strategies that enable them to achieve global coverage with reduced latency and enhanced redundancy. The recognition of NTNs (non-terrestrial technologies) and how they can complement and enhance traditional cellular networks is being realized with the deployment of initial Direct-to-Device networks from major mobile operators. The human need for connectivity and the race to ubiquity of networks is truly on. The future scenario will involve HEO, GEO, LEO and MEO, delivering the most suitable and cost-effective form of satellite connectivity wherever it is needed.
The increasingly unstable geopolitical environment is also focusing government and defense minds on multi-orbit, multi-frequency satellite capabilities, a critical and expanding part of their comms portfolio, which enables them to communicate in the most remote and hostile areas on the planet. Essentially, satellites are moving from a niche to an essential technology, with a much larger remit.
Multi-orbit networks bring with them more complexity, and this puts more demand onto the ground segment that supports the satellites. Whether they are used as ground stations or are portable and operated by a non-technical person, they must be more capable than ever, and operate whenever and wherever the user needs them, regardless of the environment, location, or application.
How is the multi-orbit environment challenging ground terminal design and what kind of innovation is required to overcome these hurdles?
Technical challenges for ground terminal manufacturers
We have come a long way from legacy GEO networks already, adding in the complexity of other orbits, but for the manufacturers of ground terminals, there are a number of complex engineering hurdles that must be overcome when designing and manufacturing antenna systems for multi-orbit, multi-use networks that center around the ability to track and signal management.
Tracking, locking on and handing over
The velocities of both LEO and MEO satellites vary greatly, something with which traditional AZ/EL terminals struggle. Additionally, each satellite can only be visible for a short while from any ground location before it drops over the horizon. The constant switching to track one satellite to the next without dropping any data can be challenging. This is why X/Y antennas have the edge.
Managing multiple frequency bands
Terminals must also be able to switch between multiple frequency bands as and when required. Whilst LEO satellites utilizes the Ku- and Ka-band frequencies, GEO tends to utilize a wider variety of bands such as C-, Ku-, Ka-, L- and X bands and MEO utilizes mostly Ka-band. This means that a single terminal needs to cover a wide variety of bands. Though there has been a focus on the potential use of Q/V bands for very high throughput, this is less common and the most popular high frequency band remains Ka- as Q/V-band equipment is still very expensive to develop.
Overcoming technical hurdles
Antennas that facilitate multi-orbit connectivity are in high demand and must offer flexibility and versatility. The defense sector especially is looking at the next generation terminals to enable it to be more agile and access multi-orbit, multi-frequency networks to meet their stringent and wide-ranging requirements.
X/Y terminals allow multi-orbit connectivity through their versatile tracking system that uses two perpendicular horizontal axes instead of a rotating base. This allows these antennas to track a satellite overhead without hitting a zenith or keyhole blind spot. The traditional azimuth-elevation type antenna mount cannot effectively track satellites as they cannot move at the required speeds to track the satellite overhead. The X/Y rotates across two independent axes and never loses the signal at its zenith. Moreover, there are no problems with cabling, and excessive winding and pointing errors are very small, which is extremely important in the case of Ka- and Ku- frequencies.
Managing frequency successfully
The frequency challenge can be overcome with multi-band antenna systems that span from L-band all the way to Ka-band. Systems must be agile in order to operate across different frequencies and must be able to isolate transmit and receive paths during operation. They must also offer dynamic range and gain to close links with fast-moving satellites and retain high margins for GEO and MEO links. In addition, there is a risk of interference. Satellite spectrum is widely shared and therefore antenna systems must be manufactured and tested in order to mitigate instances of interference. Engineering techniques such as adaptive power control, where ground systems adjust their power dynamically; polarization isolation, where antennas adjust and isolate perpendicular radio frequency polarizations; or electronic protection where receivers apply intelligent algorithms to identify stray signals and cross-orbit interference can be effective mitigation tools.
Testing
Testing an antenna system to ensure that it complies with frequency requirements is essential. The antenna reflector is critical to the integrity of the antenna system and testing ensures seamless, high-frequency signal switching and tracking across all orbits without dropping of signals. The ability to precisely verify the reflector profile will ensure successful high data throughput. Testing also ensures that the switching between different orbits and beam steering are smooth and that the reflector is tolerant in certain conditions such as extreme temperatures or mechanical stress.
For many operators, unless a parabolic antenna is certified and has received type approval, it could be rejected for their network.
Software flexibility
Software plays a key role in antenna systems as it acts as the brain of the system and addresses the complexity of multi-orbit capability. It is essential for dynamic tracking, switching between satellites and orchestration of traffic and also for essential system functions such as adjusting slew rates (maximum angular turning speed for a tracking antenna) and acceleration curve (which is a plot of how the spacecraft acceleration changes as it passes across different orbital heights). The software must coordinate the complex steering system across each domain. With satellites moving at varying speeds it is essential that they function intelligently and with high precision.
Know your customer
The specific design of an antenna system will depend heavily on the individual customer requirements and applications they use. Getting to know the customer well and developing a close working relationship with them enables the development of a flexible system in terms of both hardware and software. This means that other elements can incrementally be integrated into the product.
The talent pool within antenna manufacturing is its heartbeat. Seeking out the very best employees in hardware and software design and ensuring they are nurtured helps to feed innovation and creative thinking. Selecting a manufacturer with heritage and long experience in the design and manufacture of antenna systems is the key consideration. This will give the customer assurance there is access to a proven and reliable supply chain for associated components, materials and testing from the design phase all the way through to product completion.
The future of multi-orbit antenna manufacturing is sure to result in an increase in single-aperture, constellation-agnostic terminals that seamlessly move between orbits and provide high throughput connectivity at any location. With the defense sector, as well as aviation and maritime driving factors for multi-orbit capabilities, there is expectation of solid growth as the industry goes forward, and antenna innovation will continue to push these systems to the next level.
