Very High Throughput Satellites (V/HTS): Technology, Challenges, and Future Systems

Very High Throughput Satellites (V/HTS) are transforming the landscape of satellite communications, offering unprecedented data transmission rates that exceed 100 Gbits/second. Imagine downloading a movie in seconds, or video conferencing across continents with zero lag. This isn’t science fiction, but the potential of Very High Throughput Satellites (VHTS).

These advanced systems, equipped with spot beams, are poised to revolutionize not only commercial but also military communications by providing robust, high-speed connectivity in even the most remote locations. However, the journey to fully realizing the potential of V/HTS technology is fraught with challenges that require cutting-edge innovations and future-ready solutions. This article explores the technology, challenges, and future prospects of V/HTS systems, particularly focusing on the use of spot beams.

Understanding V/HTS Technology

V/HTS satellites leverage spot beams—focused, high-power signals directed at specific geographic areas—to dramatically increase data throughput compared to traditional broad-beam satellites. This capability allows for higher data rates, greater spectral efficiency, and improved frequency reuse, enabling a single satellite to support more users and applications simultaneously.

Satellite antenna gain is constrained by its beamwidth ( varies inversaly ) , whatever the frequency at which the link is operated. So the antenna gain is imposed by the angular width of the antenna beam covering the zone to be served. Therefore with single beam antenna coverage, it is therefore necessary to choose between either extended coverage providing service with reduced quality to geographically dispersed earth stations, or reduced coverage providing service with improved quality to geographically concentrated earth stations.

Multibeam antenna coverage allows these two alternatives to be reconciled. Satellite extended coverage may be achieved by means of the juxtaposition of several narrow beam coverages, each beam providing an antenna gain which increases as the antenna beamwidth decreases (reduced coverage per beam).

Spot beams are a key feature of V/HTS, allowing for high-powered, localized coverage. A fundamental difference in HTS architecture is the use of multiple spot beams instead of wide beams, providing two main advantages. First, higher transmit/receive gain is achieved due to the increased directivity and gain of narrower beams, which allows for smaller user terminals and higher-order modulations, thereby increasing data transmission rates per unit of orbital spectrum. This improved link budget supports higher spectral efficiency and throughput, making Mbit/s more cost-effective.

Second, frequency reuse is enabled by covering the service area with multiple spot beams, allowing the same frequency band and polarization to be reused across different beams. In multibeam satellite, the isolation resulting from antenna directivity can be exploited to re-use the
same frequency band in separate beam coverages. This boosts the satellite system’s capacity for a given frequency allocation, exploiting antenna directivity to reuse frequencies in separate beam coverages.  As a result, higher spectral efficiency translates to higher data transmission rates per unit of orbital spectrum, addressing orbital slot congestion and spectrum limitations.

This leads to:

1. Higher Transmit/Receive Gain: Narrower beams result in increased power, enabling smaller user terminals and higher data rates per unit of orbital spectrum.
2. Ultra-High Bandwidth: VHTS boast data transfer rates exceeding 100 Gbps, dwarfing the capabilities of older satellites. This opens doors for bandwidth-intensive applications like remote surgery, real-time 4K video streaming, and large data transfers.
3. Frequency Reuse: Multiple spot beams can reuse the same frequency band and polarization, significantly boosting the satellite system’s capacity.
4. Reduced Latency: VHTS offer lower signal travel times due to their orbital positions and advanced communication protocols. This translates to near real-time data exchange, critical for applications like military communications and disaster response.

As the number of beams increases, link performance improves, although the complexity and mass of the antenna technology impose practical limits. In practice, the frequency re-use factor depends on the configuration of the service area which determines the coverage before it is provided by the satellite. If the service area consists of several widely separated regions (for example, urban areas separated by extensive rural areas), it is possible to re-use the same band in all beams. The frequency re-use factor can then attain the theoretical value of M.

The system architecture includes a Gateway (GW), a satellite, and multiple User Terminals (UTs), as illustrated in Fig. . The GW connects to the core network and serves geographically distant users through the satellite, acting as a relay. The feeder link connects the GW to the satellite, while the user link connects the satellite to the UT. In the typical star configuration shown in Fig. , the feeder link exhibits high directivity and gain. Depending on the communication direction, the link is termed the forward link (GW to UT) or reverse link (UT to GW).

High Throughput Satellites (HTS) have revolutionized commercial satellite communications over the past decade by utilizing advanced spot beam technology. These satellites offer the combined advantages of wide-beam coverage and high-powered, customizable spot beams tailored to specific applications across diverse regions. By leveraging frequency reuse and multiple spot beams, HTS systems deliver vastly increased capacity, often ranging from 2 to over 100 times that of traditional communication satellites, significantly lowering the cost per bit. While the deployment of HTS necessitates innovative ground infrastructure to maximize their benefits and manage costs, they offer a cost-effective solution compared to traditional shaped beam technology. For instance, whereas Ku-band Fixed Satellite Service (FSS) bandwidth can exceed $100 million per gigabit per second, HTS systems like ViaSat-1 can provide similar throughput for under $3 million, illustrating their potential for cost efficiency despite the initial higher costs of spot beam technology.

Frequency Selection

In the past decade, most high-throughput satellites (HTS) have operated in the Ka band, although this is not a strict requirement. By early 2017, there were at least ten Ku-band HTS projects, with three already launched and seven under construction. The choice of frequency bands for HTS systems depends on various factors, including coverage and beam size, atmospheric conditions in the service region, and the availability of a robust ecosystem of ground equipment technologies.

Typically, current-generation geostationary orbit (GEO) HTS systems utilize the Ka-band, which is less congested compared to the C/Ku-band. In fixed satellite services (FSS), the Ka-band encompasses frequencies from 19.7 to 21.2 GHz for the forward link and from 29.5 to 31 GHz for the reverse link. In contrast, land mobile satellite services (MSS) often use lower frequencies, such as the L-band (1.5 to 2.5 GHz), due to its lower signal attenuation, which allows for simpler user terminals. Although the Ka-band is more susceptible to severe atmospheric disturbances, these issues are typically short-lived and can be mitigated using Fade Mitigation Techniques (FMT).

Applications

As the connectivity industry evolves with the rapid advancement of technologies, the latest generation of space innovation, including HTS, is well-positioned to meet the growing demands of big data, 5G, and the Internet of Things (IoT). This growth is coupled with an increasing number of Low Earth Orbit (LEO) satellites, which offer high bandwidth, low latency, and cost-effective global coverage.

HTS systems cater to bandwidth-intensive services, driving the broadband market forward. They provide broadband Internet access comparable to terrestrial services in terms of cost and bandwidth. With rising consumer demand for HD and 4K streaming services, HTS systems are essential for delivering Over-The-Top (OTT) services, which are frequently accessed on smartphones and other connected devices, fulfilling the expectation of ubiquitous connectivity.

HTS systems deliver high throughput connectivity and a range of services similar to traditional legacy satellites. The primary requirement for HTS is to provide broadband Internet access to regions unserved or underserved by terrestrial technologies. This includes serving corporate and consumer users in areas where high-quality terrestrial broadband is unavailable. HTS is particularly suitable for cellular backhaul, supporting isolated base stations of terrestrial mobile networks with high-capacity links. Additionally, HTS can offer high data rate connectivity to customer platforms at sea, such as production oil fields in the North Sea, which are not connected by submarine cables.

VHTS (Very High Throughput Satellite) Systems for 5G

Very High Throughput Satellite (VHTS) systems are pivotal in supporting critical usage scenarios for 5G, offering significant advantages that enhance the overall network capabilities. One of the primary benefits is their ability to support multi-Gbps data rates for enhanced mobile broadband (eMBB) communications. VHTS systems can significantly improve data throughput, leveraging spot beam technology to deliver broadband services to end-users with bit rates exceeding terabits per second. This makes them well-suited to meet the high-capacity demands of 5G networks.

VHTS systems surpass the capacity of traditional Fixed and Mobile Satellite Services (FSS and MSS) by employing advanced multibeam coverage, polarization schemes, and frequency reuse techniques. These systems utilize higher bandwidths in the feeder link, such as the Q/V frequency bands, to achieve impressive throughput goals, with the objective of reaching 1 terabit per second per satellite in the near future. The contoured regional footprints of VHTS allow for more efficient use of the spectrum and better accommodation of traffic distributions, thus providing enhanced service flexibility.

In addition to supporting eMBB, VHTS systems are also essential for massive machine-type communications (mMTC), including SCADA and global asset tracking applications. These systems can scale to support the future demands of machine-to-machine (M2M) and Internet of Things (IoT) communications, making them crucial for the seamless integration of a wide array of connected devices. By enabling dynamic service delivery and accommodating higher demand per beam, VHTS systems ensure that 5G networks can handle the increasing data loads and diverse connectivity requirements of modern applications.

Overall, VHTS systems, with their multiple spot beams and advanced technological capabilities, are key enablers for the future rate demands of 5G. They offer unparalleled flexibility and capacity, making them indispensable for delivering high-speed, reliable broadband connectivity across various regions and supporting the expansive growth of 5G technologies.

Technology

Two 5 GHz frequency bands are available in the E-Band (71-76 GHz and 81-86 GHz) for commercial very high throughput satellite (VHTS) communication systems. While E-Band is attractive due to its abundant bandwidth and light licensing, it poses significant complexities for both the uplink and downlink. Adopting these high frequencies presents challenges in RF component and subsystem development for satellite communications (satcom) systems and test and measurement (T&M) equipment designed for E-Band operations.

At E-Band frequencies, several factors must be considered: the performance and commercial availability of components and subsystems, propagation losses (including rain and free-space loss), and antenna design for ground gateways and spacecraft. These frequencies require higher power and lower noise figure components to compensate for propagation and atmospheric attenuation. Consequently, mmWave components and subsystems for E-Band are significantly more complex, necessitating the development and qualification of RF components suitable for space.

To address these challenges, InP low noise amplifier (LNA) technology or other exotic heterojunction high bandgap materials with ultra-low noise figures are required in both spacecraft and gateways. Hughes estimates a noise figure of 2 to 3 dB for gateways and possibly up to 4 dB for spacecraft. For power amplifiers (PAs) and LNAs, the technologies under consideration include tube-based solutions and potentially solid-state PAs, with GaN playing a role depending on timing. Hughes is conducting detailed tradeoffs to determine the best technologies and manufacturers for space-qualified E-Band Tbps systems, including composite materials with precise tolerances for antennas.

Technological Innovations

VHTS systems using multibeam coverage must interconnect all network earth stations and provide interconnection of coverage areas. This adds complexity to the payload, which already has a more intricate multi-beam satellite antenna subsystem compared to single-beam satellites. Multibeam satellites are susceptible to interference, including co-channel interference (CCI) from side lobes and adjacent channel interference (ACI) due to imperfect filtering. Intra-system interference from frequency reuse can shift the link budget analysis from noise-limited to interference-dominated, severely degrading the carrier-to-interference ratio (CIR).

To mitigate interference and optimize performance, advanced signal processing is essential. This includes reducing interference among multiple beams, facilitating adaptive coverage, dynamically optimizing traffic, and sharing spectrum with terrestrial services. Flexibility in resource allocation per beam can significantly enhance service quality and reduce the cost per transmitted bit.

Advanced Beamforming and MIMO Techniques: Modern Very High Throughput Satellite (V/HTS) systems are revolutionizing satellite communications through several technological innovations, enhancing their efficiency and adaptability. One significant advancement is the use of advanced beamforming and Multiple Input Multiple Output (MIMO) techniques. These technologies are crucial for improving spectral efficiency and boosting data throughput. Advanced beamforming allows for the precise direction and shaping of radio waves, facilitating the dynamic allocation of bandwidth and power to different spot beams based on real-time demand. MIMO techniques, by utilizing multiple transmission and reception antennas, further increase the capacity and reliability of communication links, making the system more robust and efficient.

On-Board Processing and AI: On-board processing and the integration of artificial intelligence (AI) represent another leap forward for V/HTS systems. By incorporating powerful processing capabilities directly on the satellite, V/HTS can manage and optimize data traffic in real-time. AI algorithms play a critical role in this process by predicting and adjusting to fluctuating user demands, varying weather conditions, and potential interference. This real-time adaptability ensures that the satellite system maintains optimal performance, delivering high-quality service even under challenging conditions. The use of AI in on-board processing allows for more efficient resource management and enhances the overall reliability and effectiveness of the satellite communications network.

Flexible Payload Architectures: The development of flexible payload architectures, particularly those utilizing software-defined radios (SDRs), offers significant benefits for V/HTS systems. These flexible architectures enable in-orbit reconfiguration of satellites, allowing them to adapt to changing mission requirements and incorporate emerging technologies without the need for expensive and time-consuming replacements. This adaptability is crucial in a rapidly evolving technological landscape, where the ability to quickly respond to new demands and opportunities can provide a substantial competitive advantage. SDRs facilitate this flexibility by allowing modifications to the satellite’s communication protocols and capabilities through software updates rather than hardware changes.

Next-Generation Antennas: Next-generation antenna technologies are also playing a pivotal role in the advancement of V/HTS systems. Innovations such as phased array antennas and electronically steerable arrays are essential for supporting the high data rates and dynamic beam steering capabilities required by modern satellite communications. These advanced antennas offer several advantages, including improved performance, reduced size, and enhanced reliability. Phased array antennas can rapidly and precisely steer beams electronically without moving parts, making them more reliable and faster in response to changing communication needs. Electronically steerable arrays further enhance the ability to dynamically adjust beam patterns, improving the efficiency and flexibility of the satellite communication system. These technological innovations collectively drive the performance and adaptability of V/HTS systems, making them a cornerstone of modern satellite communications.

The overall performance of VHTS systems depends on applied signal processing capabilities and various system choices. High frequency reuse schemes can stress satellite payload resources in terms of mass, power, and thermal dissipation. Increasing frequency reuse also necessitates a corresponding increase in feeder link bandwidth, which can be addressed by employing multiple gateways.

VHTS systems require advanced transmission standards such as DVB-S2/S2X, which utilize high-efficiency modulation and coding schemes (MODCODs) up to 256APSK and advanced interference management techniques. DVB-S2X incorporates a super-framing structure enabling signal processing techniques like precoding and multi-user detection at user terminals. Variable coding modulation (VCM) and adaptive coding modulation (ACM) are used in the forward link of High Throughput Satellites to handle atmospheric conditions and different geographical locations, optimizing modulation and coding under dynamic conditions like rain fade.

Present and Future Systems

Current Systems

High Throughput Satellites (HTS) like ViaSat-1, SES-12, and EchoStar XVII have already demonstrated capacities exceeding 100 Gbps. These systems utilize the Ku/Ka-band frequencies for both feeder and user links, with Ka-band being particularly favored due to its less congested spectrum compared to C/Ku-bands.

Future Trends

Next-generation V/HTS systems aim to achieve throughputs in the range of terabits per second, utilizing higher frequencies such as Q/V and W-bands to support thousands of spot beams. This evolution is driven by the need to meet growing demands for bandwidth-intensive services, 5G integration, and IoT applications.

Low Earth Orbit (LEO) and Non-Geostationary Satellite Orbit (NGSO) Systems

Although Geostationary (GEO) satellites once dominated the outer orbits of the Earth, the increasing deployment of HTS GEO, MEO and LEOs, with alternative operating systems, is demanding that solutions providers adapt to vastly different requirements.  Non-geostationary orbit (NGSO) satellite system is proposed to provide low-latency, high-bitrate global Internet connectivity and several satellite constellations are about to begin commercialization. More than a dozen such satellites have been launched in recent years and several more will go into orbit in the coming years.

LEO and NGSO constellations, like SpaceX’s Starlink and OneWeb, are pivotal in the future landscape of satellite communications. These systems promise low latency, high bitrate global connectivity, and significant capacity increases, challenging the traditional dominance of GEO satellites.

Challenges and Technological Requirements

Interference and Signal Processing

The complexity of multibeam systems introduces challenges such as co-channel and adjacent channel interference. Advanced signal processing techniques are essential to mitigate these issues, ensuring optimal performance and flexibility in resource allocation.

Payload and Platform Design: The design of satellite payloads and platforms must address the need for high power, advanced thermal management, and miniaturization. High-throughput satellites require sophisticated on-board processing capabilities to manage the increased data rates and the complexity of spot beam formation and switching.

Launch and Deployment Costs: Launching V/HTS satellites into geostationary or low Earth orbits remains a significant financial and logistical challenge. Reducing the cost of launch vehicles and improving the reliability of deployment mechanisms are crucial for the economic viability of V/HTS systems.

Ground Segment Infrastructure: The ground segment, including user terminals and gateway stations, must evolve to support the high data rates provided by V/HTS. This involves the development of advanced antennas, modulation schemes, and error correction techniques to ensure efficient and reliable data transmission.

Orbital Congestion: As the number of satellites increases, so does the potential for congestion in popular orbital slots. Careful planning and international cooperation are crucial to ensuring efficient use of space.

Spectrum Management: The allocation and management of radio frequency spectrum are critical for V/HTS operations. With the ever-increasing demand for bandwidth, efficient spectrum utilization and mitigation of interference are essential. Regulatory bodies must balance the needs of various users while ensuring that V/HTS systems operate effectively.

Security and Resilience: For military applications, ensuring the security and resilience of V/HTS communications is paramount. This includes protecting against cyber threats, jamming, and physical attacks, as well as ensuring continuity of service in adverse conditions.

Frequency Selection and Atmospheric Effects

While Ka-band is commonly used, its sensitivity to atmospheric conditions necessitates Fade Mitigation Techniques (FMT) to maintain reliability. Future systems may increasingly rely on Q/V bands, though these present their own propagation challenges.

Component and Subsystem Development

Developing components and subsystems for higher frequency bands like E-Band involves overcoming significant technical hurdles. Innovations in low noise amplifiers (LNAs), power amplifiers (PAs), and antenna design are crucial for achieving the desired performance.

Tech Advancements Powering the Future

The future of VHTS is bright, with continuous advancements in key areas:

• Advanced Materials: New lightweight and high-strength materials will enable the development of even more powerful and compact VHTS payloads.
• Interference Mitigation: Advanced signal processing reduces interference among multiple beams, maintaining high-quality communications.
• On-Orbit Servicing: The ability to service and maintain satellites in space will extend their lifespans and reduce overall costs.
• Software-Defined Networking (SDN): Utilizing SDN can optimize traffic routing and network management, maximizing the efficiency of VHTS constellations.

Beyond the Lab: Real-World Deployments

The landscape of high-throughput satellites (HTS) has significantly evolved with the deployment of advanced systems that dramatically increase data capacity and coverage.

Current HTS Systems:

• ViaSat-1: Launched in October 2011, ViaSat-1 provides 140 Gbit/s capacity, surpassing the combined capacity of all other commercial communications satellites over North America at the time.
• SES-12 and EchoStar XVII (Jupiter-1): These satellites offer over 100 Gbit/s capacity, each utilizing the Ku/Ka-band in both feeder and user links, with up to 200 beams in the same frequency band.

VHTS Systems:

• Viasat-3: Aiming to achieve data rates in the range of terabits per second (Tbps), Viasat-3 operates in higher frequencies such as Q-band (30-50 GHz), V-band (50-75 GHz), and W-band (75-110 GHz). This enables it to serve up to 3000 beams in the user link, significantly enhancing capacity and flexibility.

• OneWeb Low Earth Orbit (LEO) Constellation

OneWeb Low Earth Orbit (LEO) Constellation satellite

• Technical Features:

  • Constellation of 648 LEO satellites planned (as of June 2024, 428 launched)
  • Utilizes Ku-band and S-band frequencies
  • Target download speeds of 100 Mbps to individual users
  • Focuses on providing broadband internet access to underserved areas

• SpaceX Starlink Network

SpaceX Starlink Network satellite

• Technical Features:

  • Constellation of thousands of LEO satellites planned (over 2,500 launched as of June 2024)
  • Utilizes Ku-band and Ka-band frequencies
  • Offers download speeds ranging from 25 Mbps to 220 Mbps to users
  • Aims to provide global broadband internet coverage

• Telesat Lightspeed

 

Telesat Lightspeed satellite

• Technical Features:

  • Constellation of 298 LEO satellites planned (launch expected to start in 2024)
  • Employs Ka-band frequencies
  • Designed to deliver download speeds exceeding 100 Gbps
  • Targets enterprise customers and high-bandwidth applications

• Amazon Project Kuiper

Amazon Project Kuiper satellite

• Technical Features:

  • Constellation of 3,236 LEO satellites planned (launch timeline yet to be announced)
  • Leverages a mix of low, medium, and high Earth orbit satellites
  • Specific technical details not yet fully revealed
  • Aims to provide high-speed internet access with a focus on cloud services

• These are just a few examples of the many VHTS projects currently underway. As the technology continues to develop, we can expect to see even more advanced and capable VHTS constellations launched in the coming years. The future of space communications is undoubtedly bright, and VHTS are poised to revolutionize the way we connect with each other and the world around us.

SpaceBridge Developments:

• Oman’s Multi-Service Ka-Band Network: SpaceBridge completed the delivery of a multi-service Ka-band HTS broadband satellite network to Oman’s leading operator, SCT, in October 2021. The network, supporting nearly 2000 locations, uses SpaceBridge’s WaveSwitch™ technology to provide resilient internet connectivity across various sectors including communities, enterprises, mobile network operators, maritime, consumers, government, and military entities.
• Resilience and Disaster Recovery: SpaceBridge’s VSAT network demonstrated resilience during Cyclone Shaheen in Oman, maintaining connectivity despite severe weather conditions. This highlights the robustness of modern HTS systems in providing reliable communication services during natural disasters.

Hongyan (China): The China Aerospace Science and Technology Corporation (CASC) plans to deploy nine LEO satellites as a pilot demonstration for the Hongyan system, which will ultimately comprise 320 satellites by 2025.

ISRO’s High-Throughput Satellites:

• GSAT Series: India is preparing to launch a series of high-throughput communication spacecraft, starting with GSAT-19. Project Director P.K. Gupta announced plans for GSAT-11, GSAT-20, and two next-generation spacecraft (HTS-1 and HTS-2), each with a capacity of 100 Gbit/s, covering the entire country. These satellites will incorporate new technologies such as flexible satellite assembly platforms, electric propulsion, Ka-band communication, and lithium-ion batteries, driving a next-generation technology revolution in India.

Advanced Technologies: Modern HTS systems incorporate advanced technologies such as multi-beam coverage, polarization schemes, frequency reuse, and higher bandwidths in feeder links. These innovations enable HTS systems to provide broadband services with bit rates exceeding terabits per second, supporting applications like enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and Internet of Things (IoT) communications.

Military Applications

V/HTS systems offer several advantages for military communications, including:

• Secure and Reliable Communications: VHTS can provide high-bandwidth, secure communication channels for troops in remote locations, enabling real-time data exchange and improved situational awareness.
• Increased Data Rates: Enhanced throughput supports high-bandwidth applications essential for modern military operations.
• Improved Command and Control: VHTS can facilitate faster and more reliable transmission of critical data between command centers and deployed forces, enhancing overall mission effectiveness.
• Enhanced Security: Spot beams are harder to jam, and digital payloads can quickly adapt to interference.

VHTS Market: A Booming Landscape Fueled by Skyrocketing Demand and Supply

The Very High Throughput Satellite (VHTS) market is experiencing explosive growth, driven by a surge in demand for high-speed internet connectivity and a corresponding increase in satellite capacity. Here’s a breakdown of the latest figures and estimates:

Market Demand:

• NSR and Euroconsult studies predict global demand for GEO HTS (Geostationary Earth Orbit High Throughput Satellite) services to reach a whopping 1.9 Tbps (Terabits per second) by 2024.

Market Revenue:

• Euroconsult’s research, “High Throughput Satellites: Vertical Market Analysis & Forecasts,” forecasts HTS revenue to reach a staggering $15 billion by 2028. This translates to a cumulative $85 billion in capacity leasing revenue over the next decade.

Growth Drivers:

• Nine key vertical markets are fueling this growth:
  • Consumer Broadband
  • Rural Connectivity
  • Civil Government
  • Corporate Networks & Energy
  • Military Communications
  • Cellular Backhaul & Trunking
  • Aero In-Flight Connectivity
  • Maritime Communications
  • Video Services

Demand Growth Rate:

• The report predicts a robust 26% annual growth rate for the VHTS market over the next ten years.

Supply Boom:

• With several Non-Geostationary Orbit (NGSO) HTS constellations coming online, HTS capacity is poised for unprecedented growth. Supply is expected to jump a staggering 12 times between 2019 and 2024, reaching 26,500 Gbps by 2024 (compared to just 2,100 Gbps in 2019).
• High-volume manufacturing and launch campaigns by companies like SpaceX and OneWeb are driving this supply surge.

Impact of NGSO Constellations:

• Euroconsult’s Brent Prokosh emphasizes the transformative potential of NGSO constellations. Unlike previous, more regionalized HTS deployments, these large-scale, global constellations will offer expansive coverage and flexibility, completely reshaping the HTS landscape.

Regional Demand:

• While North America is a mature and leading market, emerging markets in Asia Pacific, Latin America, and Africa are experiencing significant growth.

Demand by Service:

• Broadband services dominate demand, with forecasts predicting 1.1 Tbps of broadband delivered using Ka-band.
• Ku-band HTS capacity is expected to handle a smaller chunk at around 50 Gbps.

These figures paint a clear picture: the VHTS market is on a fast track to growth. As demand for high-speed connectivity continues to rise and next-generation satellite constellations come online, we can expect even more impressive figures and advancements in the years to come. VHTS technology holds immense potential to bridge the digital divide, empower businesses, and revolutionize communication capabilities across the globe.

Future Trends in High-Throughput Satellite Systems

Next-Generation V/HTS Systems: Future multibeam Very High Throughput Satellite (V/HTS) systems aim to achieve terabits per second (Tbps) throughputs using thousands of spot beams. The conventional radio frequency (RF) Ku-/Ka-band feeder links, between gateways and satellites, are limited by the available spectrum, which restricts their ability to achieve such high throughputs. Free Space Optical (FSO) feeder links present a promising alternative due to their higher capacity and immunity to RF spectrum congestion, and they have recently gained significant attention in the satellite community.

Emerging Trends in Space Segment:

1. Low-Earth-Orbit (LEO) Constellations: LEO satellite constellations, such as those planned by SpaceX’s Starlink and OneWeb, are set to complement the capacity provided by Geostationary Orbit (GEO) HTS. These constellations promise lower latency and enhanced coverage, particularly in underserved regions.
2. Flexible, High-Capacity GEO HTS Payloads: Innovations in GEO HTS payloads are moving towards more flexible and reconfigurable designs. This flexibility allows satellites to dynamically allocate capacity based on real-time demand, thus optimizing resource utilization and improving service delivery.

Ground Segment Innovations: The success of LEO constellations heavily relies on cost-effective, electronically steerable Flat-Panel Antennas (FPAs). These antennas can track satellite movements and seamlessly handover connections between satellites, ensuring continuous and reliable service.

Addressing Non-Uniform Traffic Demand: Current VHTS systems often assume uniform traffic demand per beam, leading to inefficient resource utilization. Some beams may have excess capacity while others are overloaded. Flexible payloads capable of reallocating resources (e.g., power, bandwidth, and beam-hopping illumination time) can address this issue. However, such flexibility significantly increases payload costs and can introduce latency due to processing time.

Software-Enabled Satellite Payloads: The trend for GEO satellites is to develop software-enabled payloads that can dynamically allocate capacity based on geographic demand. This innovation is expected to bring more flexibility and cost-efficiency to satellite operations, allowing for optimized service delivery.

Beam Hopping Technology

Concept and Benefits: Beam hopping is a technique that allows satellites to shift capacity from one beam to another in response to ground demand. Using time-division multiplexing with a single frequency, this method contrasts with older techniques that separated spot beams by frequency and polarization. Beam hopping technology offers several advantages:

• Dynamic Capacity Allocation: Satellites can measure customer data needs in real-time and adjust capacity distribution across beams accordingly. This ensures that areas with higher demand receive more capacity.
• Enhanced Mobility Services: Beam hopping is particularly beneficial for mobile applications, such as in-flight entertainment and connectivity (IFEC) systems. It allows beams to be targeted at specific air and sea routes only when needed, providing high-quality service while optimizing power use.
• Interoperability: Since beam hopping technology is part of the DVB-S2X standard, there is a high degree of interoperability among different satellite systems, regardless of the equipment vendor.

Beam Hopping Initiatives: OneWeb is leading a consortium of space companies to develop a beam-hopping satellite, funded by the UK Space Agency through the European Space Agency’s (ESA) Sunrise Program. The project has received approximately $45 million (32 million pounds) for development. The demonstration satellite, nicknamed Joey-Sat, is set for launch in 2022. It will be capable of dynamically directing beams to specific locations to meet varying demand, showcasing the practical applications and benefits of beam hopping technology.

In summary, the future of high-throughput satellite systems lies in the integration of advanced technologies such as FSO feeder links, flexible payloads, and beam hopping. These innovations will enable satellites to achieve higher capacities, improve resource utilization, and provide more reliable and responsive services to meet the growing demand for broadband connectivity.

Conclusion

V/HTS systems represent a transformative advancement in satellite communications, offering unparalleled throughput and flexibility. By leveraging spot beam technology and advanced signal processing, these systems can meet the growing demands of both commercial and military users. As technology progresses, the deployment of higher frequency bands and LEO/NGSO constellations will further enhance the capabilities of V/HTS, cementing their role in the future of global connectivity.