Introduction
Communication satellites have been used effectively in telephone communications, broadcasting of television and radio programs, mobile and military communications, and data communications. With these features, satellite communications have fostered the development of interpersonal relationships and facilitated the rapprochement of countries having diverse cultures.
Since the launch of INTELSAT, the first commercial satellite, on April 6, 1965, and its bringing into service in Geosynchronous Orbit (GEO), satellite technology had advanced rapidly, opening new horizons for humanity. The success of the launch vehicles used had significantly accelerated these developments. The wide coverage of satellites in GEO, their ease of deployment, and their greater reliability than terrestrial communication systems had been key factors in the preference for satellite communications.
As a result of the inability of terrestrial systems to meet Turkiye’s rapidly increasing needs in the field of communications, the need for national satellite communications systems that would encompass all communications services and enable people to access these services regardless of their geographic location emerged, and as a result, the seeds of the TURKSAT project were sown.
Hence, since 1994, numerous TURKSAT satellites have been placed in GEO, operating at 31, 42, and 50° East longitudes, specifically assigned to Turkiye, with specific frequencies and coverage. Turkiye’s satellite journey has continued unabated with the successful commissioning of TURKSAT 1, 2, 3, 4, and 5 series satellites. Finally, in the last quarter of last year, the TURKSAT-6A satellite, designed, produced, and tested entirely indigeniously and nationally through the collaboration of four of Turkiye’s distinguished organizations (TUBITAK Space, TAI, ASELSAN, and C-TECH) was successfully launched into space and put into service.
On the other hand, in parallel with GEO satellite projects, studies in the Low Earth Orbit (LEO), and particularly in the cubesat field, were initiated in Turkiye in the early 2000s.
When our calendars indicated September 2009, our country’s first cubesat, developed by Istanbul Technical University, was successfully launched into space.
The BILSAT LEO satellite, jointly designed and developed by the then-BILTEN (now TUBITAK Space) with the technology transfer provided by the British SSTL Company, was Turkiye’s first electro-optical Earth observation and remote sensing satellite and was launched into space in 2003.
RASAT was the first Earth observation satellite designed and built in Turkiye. It was the Turkiye’s second remote sensing satellite after BILSAT.
In later years, GOKTURK-2 satellite, Turkiye’s first high-resolution reconnaissance and observation satellite, was designed and developed nationally in cooperation with TUBITAK Space and TAI.
The aforesaid satellites were followed by GOKTURK-1 and IMECE satellites.
In the 2020s, we witnessed the commissioning of new LEO satellites developed by PLAN S and Hello Space companies, compatible with the concept of IOT (Internet of Things), and cubesats developed by Gumush company.
All of these studies, whether in GEO or LEO, are extremely important and valuable developments for our country, because it is an inevitable fact that Turkiye that is developed in every aspect must benefit from the modern opportunities and advantages of our age, including satellite and space technologies.
Reasons for the Transition from GEO to LEO and Advantages and Disadvantages of LEO Satellites
The reasons for the transition from GEO to LEO can be examined under several headings:
- Change in service types
- Increased demand for satellites
- Launch activities being easier than before with the miniaturization of satellites
- Reduced production and launch costs
- The proliferation of digital payloads
- Development and production of steerable multi-beam antennas
- Development of advanced modulation and coding techniques
- Reuse of frequencies
The advantages of LEO satellites with respect to GEO satellites can be listed as follows:
- Much more cost effective
- Shorter production and bringing into service duration
- Lower free space loss and latency
- Higher bandwidth and therefore higher data rates
- More resistant to jamming and electronic warfare
- As a result of the proliferation of off-the-shelf products/materials, access to materials becomes easier and technology can be kept up with faster
- In areas where accessibility is limited due to their geographical locations, the use of LEO satellites provides convenience for M2M (Machine to Machine) communication and IOT (Internet of Things)
Thanks to all these advantages, LEO has become a rising trend in the satellite communications market.
But along with the advantages offered by this orbit, there are also disadvantages listed below:
- A large number of satellites are required to ensure uninterrupted and seamless communication.
- Service life is much shorter.
- Very precise and fast tracking systems are required on the ground.
- A large number of Inter Satellite Links (ISL) and/or data links are needed between satellites for seamless connection.
- Due to the large number of satellites, there is undoubtedly an operational difficulty.
Usage Areas of LEO Satellites
- Border surveillance
- Monitoring of agricultural areas and agricultural products
- Monitoring of environmental and climate changes
- Management of natural disasters such as floods, earthquakes, fires, etc.
- City planning
- Intelligence
- Broadband internet services
- Mobile communications
- Internet Of Things (IOT)
- Deep space applications
When mentioning LEO satellites, we can’t ignore CubeSats, which are currently in widespread use. Cubesats have four main applications:
The harsh environment of space is the ultimate test bed. CubeSats can help test new instruments or materials and validate their readiness to be integrated into a more complex space mission. For example, a CubeSat can be used to study the performance of a new thermal imaging camera and the overall reliability of the instrument.
CubeSats can carry small science instruments to conduct an experiment or take measurements from space. For example, they can collect information on the magnetic field to better understand and predict its fluctuations in order to improve earthquake detection.
CubeSats can provide students with a unique hands-on experience in developing space missions from design to launch and operations.For example, a CubeSat can be used by students to track the movement of wild animals, by collecting radio signals emitted from collars attached to the animals.
CubeSats can be used for commercial applications, like providing telecommunications services or capturing Earth observation images. A company owning a CubeSat equipped with a camera can sell high-resolution images of the Earth to its clients in agriculture, city planning or business intelligence.
Major Satellite Systems Serving in LEO and Their Target Markets
IRIDIUM
It can be said that the American company IRIDIUM was the initiator of this initiative, launching the world’s first LEO communications system in 1998. IRIDIUM launched its first satellite as a technology demonstration and currently operates 80 LEO satellite constellations, 66 of which are active and 14 are reserves.
IRIDIUM satellites are used for worldwide voice and data communication from handheld satellite phones, satellite messenger communication devices and integrated transceivers, as well as for two-way satellite messaging service from supported conventional mobile phones. The nearly polar orbit and communication between satellites via inter-satellite links provide global service availability.
GLOBALSTAR
The world’s second LEO satellite constellation communications system is owned by the American company GLOBALSTAR, a competitor of IRIDIUM. GLOBALSTAR was established as a joint venture by LORAL and QUALCOMM, two of the largest players in the global satellite sector. GLOBALSTAR satellites provide voice and low-speed data services to handheld satellite phones. The GLOBALSTAR constellation currently includes 31 LEO satellites.
By speaking of GLOBALSTAR, we should also mention one of the most important recent developments in the satellite industry, and particularly in the field of LEO satellite systems.
This significant, even crucial, development is that Apple invested US$1.5 billion in GLOBALSTAR to enable its iPhones’ emergency SOS and messaging capabilities where cellular coverage is unavailable.
This new fund will allow GLOBALSTAR to purchase new satellites and expand its ground infrastructure. GLOBALSTAR currently operates 31 satellites and has already ordered as many as 26 satellites to replenish and upgrade its constellation in LEO.
TELESAT
Another important actor providing services in LEO is the Canadian company, TELESAT. With the TELESAT Lightspeed project, TELESAT aims to develop a highly innovative global network consisting of 198 state-of-the-art LEO satellites, all connected to each other like a spider web through inter-satellite links, seamlessly integrated with ground data networks.
The TELESAT Lightspeed satellite network will be approximately 20 times faster than today’s GEO satellites and on par with fiber networks. A key feature of the TELESAT Lightspeed network is its intelligent networking capability to dynamically allocate bandwidth to densely populated areas or areas with high traffic demand, such as airport hubs. Each TELESAT Lightspeed satellite has four 10 Gbps optical inter-satellite links (OISLs) that interconnect the constellation with laser communications, forming a global mesh network in space.
Rivada Space Networks
Another player in this field is Rivada Space Networks, headquartered in Germany. Rivada Space Networks announced plans to fly its first demonstration mission in 2026 and offer connectivity services by 2027.
The Rivada’s OuterNET network aims to be the first self-contained communications network in LEO, offering companies and governments the unique capability of communicating over a low-latency, mesh network without ever touching terrestrial internet.
The OuterNET constellation, comprised of 600 satellites and supported by inter-satellite laser links, promises to provide end-to-end global coverage, creating a cohesive global network in space. Rivada currently secured service to 33 countries through its agreements.
OuterNET aims to streamline ground-to-space communications, with each satellite featuring four high-speed optical inter-satellite links and advanced routing technology to ensure secure and efficient data transmission within the network. With this architecture, Rivada guarantees exceptional security, speed, and low latency for users everywhere.
AST SpaceMobile
AST SpaceMobile achieved a significant milestone in 2023 by successfully establishing the first-ever 5G connection for voice and data between a conventional smartphone and a satellite in space. The connection was made using a Samsung Galaxy S22 smartphone and AT&T spectrum with high download speed of 21 Mbit/s, in conjunction with AST SpaceMobile’s BlueWalker 3 satellite. To date, AST has launched 5 satellites, named BlueBird, into space.
AST SpaceMobile is developing a space-based cellular broadband network that connects directly to standard smartphones without requiring any additional hardware. To achieve this, they are designing their technology to be compatible with existing mobile phones and utilizing LEO satellites to provide the connection.
Starlink
Starlink is a satellite internet constellation built by the American satellite company SpaceX to provide satellite internet access. Starlink satellites consist of thousands of small, mass-produced satellites that operate in conjunction with ground stations. Currently, over 8,000 Starlink satellites are operating in LEO.
Starlink uses a constellation of LEO satellites to provide high-speed internet, but users require a special satellite dish (known as a “Starlink Dish”) and a Wi-Fi router to connect to the internet. This means that Starlink does not connect directly to smartphones or standard mobile devices, but provides internet service similar to traditional ISPs.
Starlink is a broadband internet service provider primarily targeting users in areas with poor or no broadband service. This includes rural and remote communities, as well as users requiring portable or off-grid internet solutions.
EUTELSAT OneWeb
EUTELSAT Group’s OneWeb is a dynamic network of 648 satellites operating 1,200 km above from the Earth in polar orbits.
While OneWeb is a competitor to Starlink, its market is primarily aimed at businesses, governments, telephone network operators, and community clusters, including the defense industry, rather than the individual local customers that Starlink targets.
Last year, OneWeb also signed an agreement with Kazakhstan’s National Railway Company to provide high-speed, low-latency internet service to passenger trains in Kazakhstan.
Project Kuiper
Similarly, Amazon has established Project Kuiper, a broadband internet service similar to EUTELSAT’s OneWeb. Project Kuiper is an initiative to increase global broadband access through a constellation of more than 3,000 satellites in LEO.
Multi-Orbit Strategy
As LEO satellite systems can be used to provide cellular and global services via low-cost satellites at extremely high data rates, they provide significant benefits to economies and governments in areas where this level of service has never been available before.
LEO satellites certainly undertake very important missions, and this orbit offers significant advantages. Thanks to their advantages, they undoubtedly play a significant role in defining the rules of the game in space.
However, we have now reached a point where the countries need to develop solutions beyond LEO and consider different orbital options in order to maintain their presence in space and to compete with countries that have proven themselves in space.
There are currently three main orbits where satellites are brought into service: Geosynchronous Orbit (GEO), Low Earth Orbit (LEO) and Medium Earth Orbit (MEO). Each orbit has its own advantages and disadvantages. When we evaluate these three orbits in terms of data rate, bandwidth, latency, reliability, equipment availability and cost, no orbit has a superiority over the others in all of these criteria. While one orbit dominates in one criterion, other orbits may dominate in another.
Therefore, to eliminate the disadvantages that arise when these three orbits are used individually, a satellite operation strategy that utilizes all three orbits simultaneously will transform existing disadvantages into advantages. The Multiple Orbit Strategy we are discussing here involves the simultaneous use of all three orbits. This new strategy will eliminate the inherent problems and challenges of each orbit.
By using satellites serving in 3 orbits within the same satellite cloud, it will be possible to provide an uninterrupted and reliable communication service for defense, aviation, maritime, energy sectors and large enterprises, and satellite resources will be used more effectively.
If seamless communication is targeted for critical mission operations, very high data rates and low latency are targeted for applications, and communication is desired everywhere in the air, on land and at sea, we can say that the Multi-Orbit Strategy will be the most suitable solution.
The Future of the Satellite Industry
- The majority of the over 6,000 satellites launched into space in the last two years are LEO satellites. Today, the LEO constellation is expanding and new initiatives are emerging every day. The entire sector, particularly satellite manufacturing, launch services and satellite-based services is facing significant change.
- Satellite manudacturing facilities will be diversified to manufacture both large and high-capacity satellites and small and low-cost satellites with a mass-production approach.
- Competition among satellite launch companies will intensify in the coming years. Satellite launch companies will seek ways to cost-effectively launch multiple satellites into orbit simultaneously by increasing loading capacity and reducing costs.
- Satellite operators that provide services to end users through their satellites will diversify their services by taking advantage of different orbits with the Multiple Orbit Strategy and will strive to strengthen their spheres of influence through collaborations they will develop for this purpose.
- Again, using the Multi-Orbit Strategy, communications services provided by GEO satellites will be complemented by satellites in LEO and MEO. This non-terrestrial space system will also be integrated with terrestrial infrastructure, enabling the establishment of more comprehensive, cost-effective and high-performance communications networks.
- We can predict that the number of satellite startups will increase further, resulting in fierce competition in the sector. Unfortunately, because not everyone will get a piece of the pie, we can say that companies having cost-effective, innovative solutions and business models will survive, and ultimately, we will see most startups close down.
- The network size and complexity of LEO constellations presents significant new challenges for network traffic engineering. The number of companies offering low-latency satellite communications via LEO satellites has increased dramatically recently, but it’s unlikely that many of these companies will survive in the near or distant future. Companies that can offer their customers the best price, performance and service diversity will continue to serve in the market, while those that fail to offer competitive solutions will vanish. In fact, we may even witness large and small companies joining forces to compete with larger companies, or larger companies acquiring smaller companies.
- Mobile service providers and satellite service providers are establishing and will continue to establish new collaborations and partnerships, particularly to expand their network coverages and improve the quality of service offered to their customers.
- As broadband internet becomes a necessity and the Internet Of Things (IOT) and sensor networks increase rapidly, we can say that there will be a significant increase in the number of devices connected to the internet or sensor networks.
Contact: koc@hedefkoc.com
