A straightforward guide to satellite communications
07-27-2026
6-Minute read
Summary
For businesses and individuals alike, satellite communications provide something unique: connectivity without borders. Whether you're in the middle of an ocean, at a remote mining site, or on a high-altitude aircraft, satellites extend communication far beyond the reach of terrestrial infrastructure.
In this guide, we’ll break down how satellite communications work, why it matters, and how different technologies shape its capabilities - to help you understand the foundations of this increasingly critical industry.
Satellite communications is one of the most powerful – and often invisible – enablers of modern connectivity, allowing information to move seamlessly across continents, oceans, and airspace, overcoming the geographic limitations that constrain terrestrial networks.
In its simplest form, satellite communication is the transfer of information using artificial satellites that have been launched into Earth's orbit, transmitting and relaying information from one place to another on Earth.
Today, satellite communication technologies are relied upon by millions of people around the world to support cellular, radio, television, broadband, commercial mobility, and military applications. To operate you need:
- Satellite network full technical ecosystem – satellites, ground stations, spectrum, and user terminals – working together to move data.
- Satellite operator - like Viasat, which facilitates the infrastructure, technology and solutions for governments, organizations, industries and ultimately individuals to relay information via satellite communications.
Why do we use satellite communications?
To understand the role of satellite communications, it helps to consider where terrestrial infrastructure falls short. Fiber optic cables and cellular networks provide extraordinary capacity and speed, but they depend on a physical infrastructure which becomes challenging and expensive when extending into sparsely populated or geographically challenging areas.
Satellite communications help to solve that problem – not as a replacement for terrestrial connectivity, but as a complementary layer, bolstering connectivity coverage in three key areas:
Global reach
A single satellite in geostationary orbit can “see” roughly a third of the Earth’s surface, enabling coverage across entire continents and oceans. This capability is essential for industries that operate beyond fixed infrastructure, such as shipping, aviation, and offshore energy.
Resilience
In disaster scenarios, terrestrial networks are often among the first systems to be disrupted. Satellite communications, by contrast, remain largely unaffected by ground-level damage, making it a critical tool for emergency response and recovery.
Mobility
Traditional networks are inherently tied to location, whereas satellite systems can connect moving assets even Beyond Visual Line of Sight (BVLOS), transforming operations that require constant visibility and communication such as fleet management, aviation safety, military operations, and global logistics.
How a satellite communication network works
At its core, the concept of a satellite communication network is simple: send a signal from a transmitter up to a satellite, which then relays it back to a receiver.
In practice, however, this process involves a carefully orchestrated system of components working together with remarkable precision.A satellite communication network consists of three interconnected elements:
- Space segment – The space-based infrastructure (communication satellites) that recieve, process and relay information
- Ground segment – The gateway station and control infrastructure briodging satellite networks and terrestrial networks
- User segment – The point where users access the network to send and recieve information via satellite user terminals and satellite enabled devices
Simple outline of data transfer through a typical two-way satellite network between a user terminal and satellite-based infrastructure.
Signal flow: uplink, processing, downlink
The communication process begins with the uplink, where a signal is transmitted from a ground station or user terminal toward the satellite. This signal is tightly focused using directional antennas and transmitted at carefully allocated frequencies to minimize interference.
Once received, the satellite handles the signal in one of two main ways:
Bent-pipe (transparent payload)
The satellite acts as a repeater, amplifying the signal and shifting it to a different frequency before retransmitting it. This is efficient and reliable, but generally offloads complexity to the ground.
Regenerative (onboard processing)
The satellite unscrambles and processes the signal before re-encoding for transmission, creating efficient use of bandwidth, improved signal quality, and, in some cases, reduced latency.
After processing, the signal is sent back to Earth via the downlink, where it is received by a gateway or terminal.
The role of ground stations
Ground infrastructure is where much of the network’s intelligence resides. Ground stations act as the bridge between satellite networks and terrestrial networks, such as the internet. They handle high-capacity data flows, manage traffic routing, and ensure that signals are correctly transmitted and received across the network.
In modern architectures, ground stations are distributed globally to reduce latency and improve resilience.
Connecting to the network: User terminals
User terminals are access points to the network. Advances in antenna design have transformed these devices - from large, fixed satellite dishes to compact, electronically steered antennas capable of tracking multiple satellites in motion.
In Internet of Things (IoT) contexts, terminals can be embedded directly into devices, enabling low-power, intermittent communication over global distances.
What makes this entire system remarkable is its ability to operate continuously across vast distances, often with signal paths spanning tens of thousands of kilometers, all while maintaining the reliability and performance required for critical communications.
Orbit paths and their impact
The performance and behavior of a satellite communication system are fundamentally shaped by the orbit in which its satellites operate. Different orbits offer differing advantages, influencing everything from latency and coverage to system complexity.
A visualisation of the three different orbits (GEO, LEO and HEO) satellites are typically placed in.
Geostationary Earth Orbit (GEO)
Geostationary satellites appear motionless from our perspective on Earth. This is because they orbit at the same speed as the planet's rotation; however, their actual velocity through space is much higher. The Earth rotates at roughly 1,040 mph (1,670 km/h) at the equator, whereas a geostationary satellite orbits at approximately 6,900 mph (11,100 km/h). Positioned at approximately 35,786 kilometers (22,236 miles) above the surface, GEO satellites are the backbone of Viasat’s multi-orbit, multi-band network.
Geostationary satellite networks support communication markets that demand high-volume data for technological advancements. These include sectors such as aviation inflight Wi-Fi, maritime operations at sea, autonomous transport, defense, broadband internet for consumers and enterprises, and IoT.
A key advantage of geostationary satellites is their operational efficiency. Ground stations can maintain constant communication without the need to track the satellites' motion, and they typically last around 15 years in service, making them well-suited for mobile satellite communications services that require seamless and reliable connectivity.
Did you know?
Although Viasat has 20+ satellites in GEO-stationary orbit, it only takes three GEO satellites to achieve global coverage.
Each GEO satellite adds more bandwidth, capacity and resilience to our network, enabling specialized services for different regions, customers, and applications, globally.
Low Earth Orbit (LEO)
LEO satellites are smaller and orbit much closer to Earth, between 160 and 2,000 kilometers (99 to 1,243 miles) above the surface, completing an orbit in approximately 90 minutes. Their compact size enables the launch of multiple satellites at one time to form a constellation – approximately 1,500 - 2,000 satellites in LEO are typically required to provide global coverage.
Operating at lower altitudes than other satellite orbits, LEO satellites offer reduced latency and a smaller, focused field of vision. Their lifespan is much shorter than that of a GEO satellite typically needing to be replaced after five years.
Highly Elliptical Orbit (HEO)
What makes HEO valuable is its ability to extend coverage to the Arctic region.
A HEO orbit is technically and conceptually different from circular orbits like GEO and LEO as its orbital mechanics affect velocity. Instead of maintaining a constant altitude, HEO satellites follow elliptical trajectories, characterized by:
- A perigee (closest point to Earth)
- An apogee (furthest point from Earth)
The two elliptical trajectories create an almost oval shaped orbital path where HEO satellites move much faster when closer to the Earth (perigee) as the gravitational pull is stronger and move more slowly when they are farther away (apogee) as the gravitational pull becomes weaker.
As a result of this, when in apogee, over the North Pole, satellites in HEO can provide better coverage, as it is visible for a longer period. To provide seamless connectivity, HEO connectivity requires two satellites in HEO orbit.
Viasat utilizes two Global Xpress satellite payloads, GX10A and 10B, in HEO orbit, which are currently the world’s first mobile broadband payloads dedicated to the Arctic region. These payloads will play a critical role in supporting government customers, with commercial maritime and aviation services expected to follow.
Bands, beams, and capacity in satellite communications
Satellite communications rely on access to the radio frequency spectrum, but it is the combination of frequency band selection, beam architecture, and capacity design that ultimately determines how powerful and scalable a network can be.
A visualization of the electromagentic specturm and it'sconnectivity applications per frequency band.
Frequency bands: defining performance potential
At a fundamental level, different frequency bands offer different performance characteristics.
Lower frequency bands operate with longer wavelengths, which allows signals to propagate reliably through atmospheric conditions such as rain, cloud cover, and even partial obstructions. This spectrum, such as L-band, is ideal for safety and mobility use cases where resiliency and reliability are critical, and lower data throughput is adequate for needs.
As frequency increases, so does the potential for capacity. Ku-band enables higher data rates and has been widely used for broadcast and enterprise connectivity as it avoids interference with terrestrial microwave systems, meaning better coverage, signal strength, and power for up and down links due to smaller equipment.
Ka-band represents a significant shift in capability. Operating at much higher frequencies, it unlocks far greater bandwidth, making it possible to deliver broadband-scale connectivity via satellite for applications that need a higher bandwidth and speeds, such as video conferencing, live streaming, high-speed internet for services like in-flight Wi-Fi, maritime operations, and multi-media applications.
As Ku- and Ka-bands operate at shorter wavelengths it makes them more susceptible to rain fade, particularly Ka-band. To mitigate this, Viasat’s Ka-band spacecraft are supported by two or more geographically separated ground stations, sometimes located in different countries allowing us to seamlessly switch traffic to an alternate ground station before weather conditions can impact customer services, maintaining continuity and reliability.
Beams and beamforming: using spectrum efficiently
While frequency bands define capacity, resiliency and speeds, beam architecture determines how efficiently spectrum is used.
Instead of broadcasting across large areas, satellites divide coverage into beams. Modern satellites use spot beams, concentrating power over smaller areas. This enables frequency reuse, allowing the same spectrum to be used across multiple beams without interference, significantly increasing total capacity.
Beamforming introduces further flexibility. With digital payloads and phased array antennas, satellites can dynamically shape and steer beams, redistributing capacity in response to demand. This allows operators to refine coverage and optimize performance in real time.
Capacity: scaling satellite networks
Capacity in satellite communications is no longer defined solely by the amount of available spectrum or the power of a satellite. It is now the result of how effectively spectrum and beams are combined and managed.
This shift is clearly illustrated by next-generation systems such as the ViaSat-3 constellation. Designed around Ka-band spectrum and advanced dynamic beamforming capabilities, ViaSat-3 satellites are engineered to deliver more than 1Tbps of global capacity that is highly flexible.
Rather than relying on static coverage patterns, these satellites are designed to dynamically allocate beams to areas of highest demand such as congested aviation corridors and maritime routes - delivering concentrated capacity where it is needed most.
Connecting the world from above
By now, the mechanics of satellite communications – from orbits and ground infrastructure to spectrum and beamforming – start to come together as a single, coordinated system. But what stands out is not just how it works, but what it enables.
Every message sent from a remote site, every aircraft connected mid-flight; every vessel navigating open water, every military mission in the field, relies on a network that exists far beyond our line of sight. It’s a layer of connectivity that quite literally sits above the world in space, bridging distances that would otherwise remain impossible to cross.
What makes satellite communication so powerful is also what makes it easy to overlook. It operates quietly and consistently in the background, linking people, systems, and industries without demanding attention. Yet without it, vast parts of the world would remain disconnected.
Understanding how it works offers a different perspective. It reveals a network not bound by geography but defined by reach- one that stretches beyond the horizon and continues to expand what connectivity means.
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