In the ever-evolving arena of modern warfare, electronic intelligence (ELINT) and communications intelligence (COMINT) play critical roles. These disciplines focus on intercepting and analyzing radar and communication signals to gather valuable intelligence, jam enemy systems, and protect one’s own assets. As nations strive for technological superiority, several countries are advancing satellite constellations dedicated to ELINT and COMINT capabilities to counter adversarial military radars and communications. Here’s a closer look at some key players and their initiatives.
In the dynamic landscape of modern warfare, Electronic Warfare (EW) plays a critical role. EW encompasses military actions involving the use of electromagnetic (EM) energy to determine, exploit, reduce, or prevent hostile use of the EM spectrum, while ensuring the friendly use of the spectrum.
Understanding the Components of Electronic Warfare
EW consists of three related sectors: Electronic Protection (EP), Electronic Attack (EA), and Electronic Support (ES).
- Electronic Protection (EP): Involves measures taken to protect personnel, facilities, and equipment from any effects of friendly or enemy use of the EM spectrum.
- Electronic Attack (EA): Includes actions taken to degrade, neutralize, or destroy enemy combat capability through the use of EM energy.
- Electronic Support (ES): Entails the passive detection of EM emissions from radar systems to classify and geo-locate radar systems operated by an adversary, supplying the necessary intelligence and threat recognition for effective EA and EP.
Signal Intelligence (SIGINT) and its Subcategories
SIGINT involves the interception of signals broadcasted by communication systems, radars, and other electronic systems. It is divided into:
- Electronic Intelligence (ELINT): Focuses on radar signals, analyzing frequency, modulation, bandwidth, power levels, and emitter locations.
- Communications Intelligence (COMINT): Involves the interception and analysis of communication signals.
- Foreign Instrumentation Signals Intelligence (FISINT): Involves intercepting and analyzing telemetry signals from missiles and other systems.
Historical Context and Conventional SIGINT Systems
The use of SIGINT systems can be traced back to the Arab-Israeli War of 1974, where they were utilized to monitor air defenseradars, command posts, and radio communications, including intercepting conversations of Arab pilots.
Conventional SIGINT systems include ground stations, combat aircraft carrying specialized SIGINT equipment, unmanned aerial vehicles, dedicated SIGINT aircraft, and AEWCS. However, these systems have limitations such as restricted visibility due to the line-of-sight requirement, high costs, vulnerability to missile attacks, and diplomatic issues arising from airspace violations.
Ground-based SIGINT system has a very limited visibility as SIGINT requires line-of-sight to the emitter. Manned SIGINT aircraft are very expensive and prone to missile attacks. Losing even one AEWCS represents a huge blow – financial and strategic. Area of operation is limited. The UAV based SIGINT is prone to both missile and jamming attacks. Violation of airspace strains diplomatic relations.
Advantages of Space-Based SIGINT Systems
To overcome the limitations of conventional systems, many countries are turning to space-based SIGINT systems. These systems can be deployed in various orbits depending on the type of signals they are designed to detect. For instance, low-earth orbit (LEO) satellites are used to detect low-power radar signals, while geostationary earth orbit (GEO) satellites are used to analyze high-power early warning radars.
SIGINT satellites can be deployed in various orbits depending on the type of signals the satellite is designed for, e.g. To detect low power radar signals, the satellite has to be placed in low-earth orbit while high power early warning radars can be analyzed using a satellite stationed in geostationary earth orbit. The operational orbit of the satellite can be optimized to achieve optimum dwell time over a specific area. Another important factor determining the orbit of a SIGINT satellite is the size of the antenna and the sensitivity of receiving equipment. Space based communications intelligence assets may be placed in low Earth orbit (LEO -below 2000 km) or in geosynchronous orbit (GEO). Each has its advantages and disadvantages.
- LEO COMINT Satellites: These satellites monitor low-power transmissions with short ranges and specific antenna beam patterns. They pass close to the transmitter of interest but have a limited view time of about 10 to 20 minutes per pass, requiring frequent retasking to cover different segments of the radio spectrum. LEO satellites may approach as close as 300 km above a transmitter of interest and within about 1000 km in the horizontal beam of a signal. In contrast to this, LEOsats will only have a particular area of the Earth in sight for less than 10 to 20 minutes, and also must record and store any signals of interest for later download when over a control station. The short time available for download (10 to 20 minutes say 4 times a day) severely limits the spectral bandwidth that can be monitored by a LEO COMINT asset. Such satellites must thus be frequently retasked to monitor different small segments of the total radio spectrum.
- GEO COMINT Satellites: Positioned 36,000 km above Earth, these satellites can monitor a large part of the Earth’s surface continuously and downlink data in real-time. They cover almost the entire radio spectrum but require large antennas to detect low-power signals due to their high altitude. A satellite in geosynchronous orbit can see approximately one third of the Earth’s surface and it remains stationary or nearly so with respect to a ground station. This allows such a satellite to monitor a large part of the Earth’s surface and to continuously downlink to a fixed station in ‘friendly’ territory. Because of this, almost the entire radio spectrum may be monitored and downlinked in real-time. However, the downlink frequency must be extremely high to cope with such a wide bandwidth. This necessitates the use of frequencies that are subject to significant attenuation by water vapour in the Earth’s atmosphere, and the placement of ground stations in low rainfall areas is often desirable. The disadvantage of geosychronous orbit is that the sensor is always at a great distance (a minimum of 36,000 km) from the desired signal. This implies a need for very large receive antennae, if low power signals are to be received.
The Rise of Satellite Constellations
While traditional, single ELINT/COMINT satellites exist, the future lies in constellations. These networks of multiple satellites offer several advantages:
- Persistent Coverage: With multiple satellites in orbit, a constellation can provide continuous monitoring of a particular region, unlike a single satellite with limited coverage time.
- Improved Accuracy: By triangulating signals from multiple satellites, constellations can pinpoint the origin of electronic emissions with greater precision.
- Enhanced Flexibility: Different satellites within a constellation can be specialized for various tasks, allowing for broader intelligence gathering capabilities.
Country-Specific Initiatives in Space-Based SIGINT
1. United States
The United States has long been a leader in space-based intelligence capabilities. The U.S. has a long history of deploying sophisticated SIGINT satellites. Notable examples include the Orion satellites, which are equipped with large, unfurlable antennas capable of detecting signals from small radios. These satellites play a crucial role in intercepting missile telemetry and monitoring microwave communications.The National Reconnaissance Office (NRO) and the National Security Agency (NSA) are at the forefront of developing and deploying advanced ELINT and COMINT satellites.
- Key Programs:
- Trumpet Satellites: Part of the Orion series, these satellites are believed to be designed for ELINT and SIGINT (signals intelligence) purposes, intercepting a wide range of electronic emissions.
- Advanced Orion Satellites: These next-generation satellites enhance ELINT capabilities with improved signal processing and geolocation accuracy. It is believed that US space based COMINT assets have deployed the largest space structures ever made, as antennae, some around 40m in diameter. American SIGINT satellite Orion has a 255 feet diameter unfurlable antenna which can detect signals from a wristwatch-sized radio. Orion satellites are used for intercepting missile telemetry/datalink signals and monitoring microwave traffic.
2. Russia
Russia has also invested heavily in its space-based intelligence infrastructure, focusing on countering NATO’s capabilities and enhancing its own electronic warfare (EW) assets. Russia’s Liana network is designed to locate ground-level radio signal emissions from various targets, including stationary and moving objects. The Liana system includes Lotos-S satellites for ground surveillance and Pion-NKS satellites for monitoring sea-based activities. This network is a modern iteration of the Soviet-era Legenda system, which targeted U.S. and NATO carrier groups.
- Key Programs:
- Liana Satellite System: This system includes the Lotos and Pion-NKS satellites, designed to intercept and analyze radar and communication signals from military installations and mobile units.
- Tselina-2: An older but still relevant series of ELINT satellites that complement Russia’s comprehensive space-based intelligence network.
3. China
China has rapidly developed its space capabilities, including a robust portfolio of ELINT and COMINT satellites to monitor and counter regional adversaries, especially in the Indo-Pacific region. China has been actively developing its SIGINT capabilities with the launch of the Yaogan satellite series.
China’s ELINT (Electronic Intelligence) satellites play a crucial role in detecting and identifying radar signals emitted by ships. These satellites provide essential data to Electro-Optical (EO) and Synthetic Aperture Radar (SAR) satellites, enabling them to track ships that might threaten China’s core interests. As the backbone of China’s Anti-Access/Area Denial (A2/AD) strategy, the ELINT program has evolved significantly since the launch of the first satellite in 1970.
- Key Programs:
- Yaogan Satellites: These dual-purpose satellites serve both military and civilian roles. Several variants, such as Yaogan-30, are specifically tailored for ELINT missions, intercepting electronic signals over wide areas. In March 2010, China launched its first triplet of ELINT satellites into an 1100 km, 63.4-degree inclination orbit, mirroring the early US Ocean Surveillance System. Since then, China has consistently maintained at least three operational Yaogan ELINT clusters, with five triplet clusters launched since 2010. The Yaogan constellation has evolved to include both triplet clusters and two-satellite clusters, providing comprehensive coverage and intelligence gathering capabilities.
- Shijian Satellites: Often used for technology demonstration, some Shijian satellites are equipped with advanced sensors for electronic intelligence gathering. China is transitioning from the three-satellite Yaogan ELINT clusters to a two-satellite configuration, similar to the US model. The Shijian-16-01, launched in October 2015, is the first in this new series, succeeding the Shijian-6 series, which included four pairs of satellites launched between 2004 and 2010.China’s Shijian-16 satellites are designed to spy on U.S. military activities in Asia. These satellites intercept encrypted signals from the U.S. military and analyze them to gain strategic advantages.
France, a leading member of the European Union and NATO, has developed sophisticated space-based intelligence capabilities to support its defense strategy. France is advancing its SIGINT capabilities with the CERES (Capacité de Renseignement Électromagnétique Spatiale) satellite system.
- Key Programs:
- CERES (CapacitÉ de Renseignement Électromagnétique Spatiale): This constellation of satellites is designed to perform ELINT missions, detecting and geolocating radar and communication signals across the globe. CERES constellation consists of three satellites designed to detect, locate, and characterize electromagnetic signals. The all-weather CERES satellites will carry signals intelligence payloads to detect high-frequency radio waves and other electronic signals. All information captured by the payloads will be down-linked for processing by the associated ground segment.
- The CERES constellation will be located in low Earth orbit at an inclination between 70° and 80°, to detect and locate electromagnetic signals simultaneously at different time intervals. The satellites will be positioned in a triangle shape (satellite 1 / satellite 2, satellite 2 / satellite 3, and satellite 1 / satellite 3) in close proximity to each other. They will be powered by deployable solar arrays and batteries. The ground control unit consists of two systems, one to command and control the spacecraft and the other to perform mission planning and data processing.The system aims to provide space-based early warning and ballistic missile detection capabilities for the French Armed Forces, improving situational awareness and battlefield security.
5. India
India has been enhancing its military capabilities, including the development of space-based ELINT and COMINT satellites to bolster its defense and strategic deterrence.
- Key Programs:
- EMISAT: Launched in 2019, this satellite is designed for electromagnetic intelligence, focusing on signal interception and analysis. It marks India’s significant step towards indigenous ELINT capabilities.
India’s EMISAT, developed by ISRO and DRDO, is a small ELINT satellite designed to intercept and analyze radar signals. Launched in a highly elliptical orbit, EMISAT enhances India’s intelligence capabilities by providing extended dwell times over specific areas of interest, thus improving the nation’s electronic warfare and intelligence gathering operations.
6. Israel
Israel is renowned for its advanced defense technologies and has developed satellite capabilities to gather critical intelligence on regional threats.
- Key Programs:
- Ofek Satellites: These reconnaissance satellites include ELINT capabilities, providing Israel with real-time intelligence on electronic emissions from adversarial territories.
Commercial and Private Sector Involvement
Luxembourg’s Kleos
Kleos, a start-up in Luxembourg, aims to sell geolocated radio frequency (RF) data as an intelligence service to defense ministries and security stakeholders. Kleos plans to use small satellites flying in low-orbit formation to collect RF data. This scalable solution will provide users with geolocation maps and intelligence updates, potentially revolutionizing commercial SIGINT services.
Kleos, a promising start-up based in Luxembourg, is pioneering a novel approach to providing geolocated radio frequency (RF) data as an intelligence service. Targeting ministries of defence (MoDs) and other security stakeholders, Kleos plans to use small satellites in low Earth orbit to collect and deliver critical RF data. This innovative solution can be scaled to meet varying customer demands, marking a significant advancement in the field of Signals Intelligence (SIGINT).
Innovative Satellite Constellation Strategy
Kleos’ strategy involves deploying nano-satellites, each weighing approximately 9 kg, into a low-altitude polar orbit. The initial cluster of these satellites is being constructed by Danish company GomSpace A/S and will be launched by the US aerospace company Rocket Lab from New Zealand in June 2019. A second cluster is scheduled for launch by the end of the year. These satellites will fly in formation, separated by 50–100 km, a distance optimized for differential, time-based surveillance and signal measurement, also known as multilateration.
“Essentially, each satellite will act as a sensor,” explained Bowyer, a company official, “and the cluster will function as a giant multi-headed antenna capable of collecting a wide range of RF signals.” These signals include those from satellite phones, mobile phones, maritime VHF, radars, defense systems, and even walkie-talkies on ships that have turned off their official Automatic Identification System (AIS) signals.
Data Processing and Geolocation Mapping
The collected data will undergo rigorous separation to determine whether it represents one or multiple signals layered together. This process, although complex, will enable Kleos to produce geolocation maps with increasing refresh rates, depending on the number of satellite clusters deployed.
With a single satellite cluster, Kleos’ data refresh rate will be every 10–24 hours, based on the transmission power of the targeted signals. This refresh rate will improve significantly with more clusters, reaching 0.5–2.5 hours with 10 clusters and potentially real-time refresh with 20 clusters. Ideally, a mini-constellation of five clusters will achieve a 1–5 hour revisit time, which is the initial goal.
Importance of ELINT/COMINT Satellites
Modern militaries rely heavily on electronic communication and radar systems. These emissions, while invisible to the naked eye, paint a picture of an adversary’s operations. By analyzing these electronic signals, nations can:
- Identify and track radar installations: Understand the capabilities and deployment of air defense systems.
- Decipher communication patterns: Gain insights into troop movements, command structures, and potential military actions.
- Detect new weapon systems: Identify potential threats based on unique electronic signatures.
The development of ELINT and COMINT satellite constellations is driven by the need to gain strategic advantages in modern warfare. These satellites provide several key benefits:
- Real-Time Intelligence: Rapid interception and analysis of enemy communications and radar emissions allow for timely decision-making.
- Electronic Warfare: Understanding the electronic order of battle (EOB) helps in devising countermeasures and electronic attacks to disrupt enemy operations.
- Situational Awareness: Continuous monitoring of electromagnetic spectra ensures comprehensive situational awareness, vital for defense planning and operational execution.
- Protection: These satellites help protect national assets by identifying potential threats and enabling preemptive measures.
The Future of Space-Based Espionage
The competition for space-based intelligence gathering is intensifying. As technology progresses, we can expect to see:
- Miniaturization of Satellites: Smaller satellites will allow for larger constellations, further enhancing coverage and flexibility.
- Advanced Signal Processing: Machine learning algorithms will play a bigger role in analyzing vast amounts of data collected by the constellations, leading to faster and more accurate intelligence extraction.
- International Cooperation and Competition: Collaboration between friendly nations for broader coverage and increased capabilities is a possibility, while competition for space dominance will likely continue.
The Implications: A Double-Edged Sword
Satellite ELINT/COMINT constellations offer significant advantages for national security. However, concerns remain:
- Escalation of Tensions: The ease of monitoring adversary activities could heighten tensions and potentially lead to miscalculations.
- Space Debris: The proliferation of satellites in orbit increases the risk of collisions, creating a debris field that could hinder future space exploration and operations.
- International Norms and Regulations: Clear international guidelines are needed to govern the responsible use of these powerful tools and avoid weaponization of space.
Conclusion
As the geopolitical landscape becomes more complex, the importance of advanced ELINT and COMINT capabilities cannot be overstated. Countries are investing heavily in space-based intelligence assets to ensure they stay ahead in the information warfare domain. These efforts not only enhance national security but also contribute to the stability of global strategic balances.
These systems offer unparalleled intelligence gathering capabilities, enhancing national security and strategic advantage in modern warfare. The future of electronic warfare will undoubtedly see further integration of space-based assets, driven by both governmental initiatives and private sector innovations. The future will likely see further advancements in satellite technologies, with increased automation, artificial intelligence integration, and real-time processing capabilities, continuing to revolutionize how nations conduct electronic and communication intelligence.
References and resources also include:
https://www.airforce-technology.com/projects/ceres-sigint-satellite-system/
https://janes.ihs.com/InternationalDefenceReview/
https://mark20x.blogspot.com/2018/12/isros-emisat-electronic-spy-in-space.html