Home Articles Measuring Micro-Debris in LEO with Next-Gen Space Radar

Measuring Micro-Debris in LEO with Next-Gen Space Radar

Measuring micro-debris in real-time and enabling a safer LEO with next generation space radar
Richard Jacklin, Commercial Lead
Written by Richard Jacklin

Commercial Lead

Measuring Micro-Debris in LEO with Next-Gen Space Radar

Richard Jacklin, Commercial Business Development Lead at Plextek, discusses the next frontier in space debris detection state-of-the-art mmWave radar technology  

The increasing congestion of Low Earth Orbit (LEO) is a growing challenge for satellite operators, space agencies and commercial aerospace firms. With the rapid expansion of satellite constellations and the accumulation of spent rocket stages, defunct satellites, and fragmented debris, the risk of orbital collisions has never been greater.  

Even the smallest particles – some no larger than a grain of sand – pose a serious threat to operational satellites and crewed missions. A single one-gram fragment travelling at orbital velocities has a kinetic energy one hundred times greater than that of a 9 mm bullet fired at ground level.   

The difficulty lies in detecting micro debris and understanding their densities at LEO altitudes before they cause damage, as traditional ground-based systems struggle to monitor anything below 10 cm in size. The lack of real-time, high-resolution debris monitoring creates a dangerous blind spot, leaving mission planners with incomplete data and limited options for avoidance or mitigation.  

Addressing this challenge requires a shift in approach, with a need to move away from reliance on terrestrial observation and towards on-board detection technologies that can provide real-time data of the debris environment, improving the theoretical models that we have today.   

Europe’s ESA Zero Debris Initiative sets an ambitious target: to significantly limit the production of debris in Earth and Lunar orbits by 2030 for all future missions, programmes and activities.  

While much of the conversation around compliance focuses on deorbiting strategies and spacecraft disposal, real-time debris awareness is equally critical to the success of this initiative and is an essential part of ESA’s Zero Debris plan.   

Radar technology operating at millimetre-wave frequencies can align with these objectives by offering continuous, high-resolution debris detection, enabling mission planners to navigate the evolving orbital landscape with greater precision.   

By identifying high-density debris fields, operators can adjust orbital trajectories, enhance shielding strategies, and contribute to a more sustainable approach to space traffic management.   

This data can also feed directly into ESA’s wider space situational awareness programmes, improving predictive debris modelling and reinforcing Europe’s leadership in responsible space operations.  

The implications for the North America market are equally significant.   

With NASA investing heavily in space situational awareness and debris mitigation, and the US Space Force prioritising domain awareness capabilities, the demand for more precise, space-based tracking solutions is increasing.   

Current US tracking infrastructure, while effective for larger objects, lacks the resolution and responsiveness needed for sub-millimetre debris detection.   

Private aerospace firms, including SpaceX’s StarLink, Amazon’s Project Kuiper, and Telesat’s Lightspeed, are under increasing regulatory scrutiny regarding their role in mitigating orbital congestion. As satellite mega constellations grow, real-time debris awareness is shifting from a strategic advantage to an operational necessity.  

By integrating debris detecting radar technology into more satellites at different altitudes, operators can improve their orbital decision making, enhance fleet resilience and may even lower their insurance! It’s not just satellites; North American companies are also pioneering the next generation of orbital space station with a whole suite of new transport and in-orbit servicing offerings; all needing detailed knowledge about the LEO environment.  

A debris detection step-change 

A millimetre-wave radar system can detect sub-millimetre debris in orbit. This technology represents a step-change in the industry’s ability to monitor and assess the risks posed by even the smallest fragments, offering an unprecedented level of insight into the density and distribution of micro-debris.  

Unlike traditional space surveillance methods, using in-orbit impact plates or ground based radar which can only see larger objects, millimetre-wave radar offers a high-frequency, non-impact sensing capability. Installed as a compact satellite payload, it continuously scans through a defined beamwidth, identifying debris as it passes through the radar’s field of view.   

With the ability to detect objects as small as one millimetre, the system allows for real-time data collection, giving mission planners and operators a far clearer picture of the orbital environment in which they operate. This approach enhances collision risk modelling, supports adaptive shielding designs, and provides crucial data for space traffic management strategies.  

Adaptability 

A key advantage is its adaptability. Designed as a lightweight, low-power payload, it can be integrated into satellites either as a dedicated debris-tracking module or as part of a multi-mission platform. The ability to deploy this technology on a wider scale presents a significant opportunity to improve orbital safety without adding substantial weight or cost to missions. It also supports international efforts to address the issue of space debris, aligning with initiatives such as the European Space Agency’s Zero Debris Initiative and broader global discussions around sustainable space operations.  

The reality is that space debris is not just a passive threat.   

The continued increase in the number of satellites, particularly in LEO, raises the risk of cascading collision events that could dramatically worsen the debris problem. By improving detection at the smallest scale, it becomes possible to refine mitigation strategies, ensuring that avoidance manoeuvres, shielding designs, and even active debris removal efforts are based on the most accurate data available. As the industry moves towards a more sustainable approach to space operations, better tracking and understanding of debris environments will become an essential factor in mission planning.  

While detection is a crucial first step, the real value of such technology lies in its ability to feed directly into wider debris management efforts. By mapping debris fields in real time, operators can take a more proactive approach to space traffic control, reducing the risks of collision through accurate forecasting and early intervention.   

However, the challenge of bringing new space technologies to market is well known. The complexity of developing systems that can withstand the harsh conditions of space, from extreme temperature fluctuations to prolonged radiation exposure, requires rigorous testing and qualification processes. Plextek’s radar technology must be designed with these challenges in mind, also incorporating radiation mitigating measures, not just in the electronics but also in the configuration of the antenna aperture and waveguides.   

The move towards more precise, cost-effective, and real-time debris monitoring is an inevitable evolution for the industry. As satellite operators and space agencies confront the growing complexity of the orbital environment, the need for high-resolution, real-time sensing capabilities will only increase. A system capable of detecting and analysing debris at this level will become an integral part of future space operations, contributing to safer, more sustainable use of Earth’s orbit. The implications are far-reaching, from enhanced mission planning and spacecraft protection to potential integration with emerging active debris handling technologies.  

For organisations seeking to enhance their orbital safety, improve space situational awareness, and risk reduce their missions against the growing debris challenge, now is the time to explore next-generation sensing technologies.   

The ongoing work in this field represents a critical step forward, offering a scalable, real-time solution to one of the most pressing challenges in spaceflight. As the industry moves towards a future of sustainable orbital operations, next generation sensing technologies will be fundamental to ensuring long-term space safety.  

A golden opportunity to shape the future of orbital debris management is here, and collaboration across the industry will be essential in turning innovative sensing technologies into the new standard for space safety.  

Game-Changing Radar for CLEAR missions

Game-Changing Radar for the CLEAR Mission

Developing vital radar technology for the CLEAR mission, advancing space debris removal techniques to safeguard operational satellites and spacecraft.

Plextek's white paper Sensing in Space

mmWave Technology for Space Sensing and Operations

Discover our advanced mmWave radar platform for safer and more efficient space missions.

Contact Plextek | Employees check their contact emails on a tablet

Got a project in mind?

Let’s talk

If you have got a project to discuss, or even just an idea, let's talk

Measuring micro-debris in real-time and enabling a safer LEO with next generation space radar
Measuring Micro-Debris in LEO with Next-Gen Space Radar

Detecting micro-debris in real-time is key to safer space operations. Next-gen mmWave radar technology enables high-resolution tracking of even the smallest fragments in LEO, reducing collision risks and enhancing space situational awareness. Discover how this innovation supports a more sustainable orbital future.

Kevin Cobley discussing 5G and the role of Non-Terrestrial Networks
The Future of Connectivity: 5G, 6G, and Space-Based Networks

As industries push the boundaries of global connectivity, the integration of 5G and drive towards 6G with satellite and space-based networks is unlocking new opportunities. Kevin Cobley, an expert in this evolving field, shares his insights on the challenges and innovations shaping the future of non-terrestrial networks (NTN).

Optimizing mmWave radar capabilities with Texas Instruments
Optimizing mmWave radar capabilities with Texas Instruments

Plextek and Texas Instruments: Optimizing mmWave radar capabilities to solve key design challenges

Augmenting UAV Safety with Ubiquitous Radar Technology
Augmenting UAV Safety with Ubiquitous Radar Technology

Enhancing UAV safety with ubiquitous radar tech for detect and avoid capabilities in shared airspace.

Simulated 3D radiation pattern for HF multiple-tuned antenna
Efficient Multiple-Tuned Antenna for HF Comms

Developing innovative, compact and efficient multiple-tuned antenna for HF communications, enhancing connectivity in challenging environments.

Urban Challenges Rapid RF Propagation Modelling
Urban Challenges: Rapid RF Propagation Modelling

Discover the challenges and solutions for accurately modelling RF propagation in urban settings. Explore the innovative neural network model revolutionising urban RF systems.

Plextek's white paper Sensing in Space
mmWave Technology for Space Sensing and Operations

Discover our advanced mmWave radar platform for safer and more efficient space missions.

Enhancing communication and safety in mining: the role of custom RF system design

We explore the role of custom RF system design in communication and safety within the mining industry, ensuring robust data handling and operational efficiency in challenging conditions.

High-Performance mm-Wave Radar System for in-orbit micro-debris detection - capable of detecting fast-moving particles with relative velocities of up to 15.2 km/s at distances over 60 metres away
Continuing to Lead in Radar Development for Pioneering CLEAR Mission

We continue to advance radar technology for the CLEAR mission, reinforcing the partnership with ClearSpace and the UK Space Agency for sustainable space safety and debris removal.

Revolutionising chronic pain management
Revolutionising chronic pain management

Fusing mmWave technology and healthcare innovation to devise a ground-breaking, non-invasive pain management solution, demonstrating our commitment to advancing healthtech.

An artistic impression of the CLEAR mission. © ClearSpace
Pioneering Advanced In-Orbit Servicing

Pioneering a ground-breaking collaboration in advanced in-orbit servicing, setting new benchmarks for space debris removal and satellite maintenance.

A visual representation of: SSL The Revolution Will Not Be Supervised
SSL: The Revolution Will Not Be Supervised

Exploring the cutting-edge possibilities of Self-Supervised Learning (SSL) in machine learning architectures, revealing new potential for automatic feature learning without labelled datasets in niche and under-represented domains.

Technical Papers

View All
Sensing in space The untapped potential of radar for space-based sensing. And how to get it right.
Sensing in space

Space holds vast promise. Orbiting satellites have already enabled global communications and allowed us to learn about our planet's climate. This paper will explain radar, how it works, and why it is suited to space applications. It will also discuss considerations for space companies when deploying any sensing technology. There is no one-size-fits-all when it comes to sensing. Our team works with space missions to assess if mmWave radar is right, and where it is, identify optimal configurations, software, and security to deliver against the performance and SWaP-C goals.

an image of our technical paper
mmWave Imaging Radar

Camera systems are in widespread use as sensors that provide information about the surrounding environment. But this can struggle with image interpretation in complex scenarios. In contrast, mmWave radar technology offers a more straightforward view of the geometry and motion of objects, making it valuable for applications like autonomous vehicles, where radar aids in mapping surroundings and detecting obstacles. Radar’s ability to provide direct 3D location data and motion detection through Doppler effects is advantageous, though traditionally expensive and bulky. Advances in SiGe device integration are producing more compact and cost-effective radar solutions. Plextek aims to develop mm-wave radar prototypes that balance cost, size, weight, power, and real-time data processing for diverse applications, including autonomous vehicles, human-computer interfaces, transport systems, and building security.

an image of our technical paper
Low Cost Millimeter Wave Radio frequency Sensors

This paper presents a range of novel low-cost millimeter-wave radio-frequency sensors that have been developed using the latest advances in commercially available electronic chip-sets. The recent emergence of low-cost, single chip silicon germanium transceiver modules combined with license exempt usage bands is creating a new area in which sensors can be developed. Three example systems using this technology are discussed, including: gas spectroscopy at stand off distances, non-invasive dielectric material characterization and high performance micro radar.

an image of our technical paper
Ku-Band Metamaterial Flat-Panel Antenna for Satcom

This technical paper by Dr. Rabbani and his team presents research on metamaterial-based, high-gain, flat-panel antennas for Ku-band satellite communications. The study focuses on leveraging the unique electromagnetic properties of metamaterials to enhance the performance of flat-panel antenna designs, aiming for compact structures with high gain and efficiency. The research outlines the design methodology involving multi-layer metasurfaces and leaky-wave antennas to achieve a compact antenna system with a realised gain greater than +20 dBi and an operational bandwidth of 200 MHz. Simulations results confirm the antenna's high efficiency and performance within the specified Ku-band frequency range. Significant findings include the antenna's potential for application in low-cost satellite communication systems and its capabilities for THz spectrum operations through design modifications. The paper provides a detailed technical roadmap of the design process, supported by diagrams, simulation results, and references to prior work in the field. This paper contributes to the advancement of antenna technology and metamaterial applications in satellite communications, offering valuable insights for researchers and professionals in telecommunications.

an image of our technical paper
The Kootwijk VLF Antenna: A Numerical Model

A comprehensive analysis of the historical Kootwijk VLF (Very Low Frequency, which covers 3-30 kHz) antenna, including the development of a numerical model to gain insight into its operation. The Kootwijk VLF antenna played a significant role in long-range communication during the early 20th century. The paper addresses the challenge of accurately modelling this electrically small antenna due to limited historical technical information and its complex design. The main goal is to understand if the antenna’s radiation efficiency might explain why “results were disappointing” for the Kootwijk to Malabar (Indonesia) communications link. Through simulations and comparisons with historical records, the numerical model reveals that the Kootwijk VLF antenna had a low radiation efficiency – about 8.9% – for such a long-distance link. This work discusses additional loss mechanisms in the antenna system that might not have been considered previously, including increased transmission-line losses as a result of impedance mismatch, wires having a lower effective conductivity than copper and inductor quality factors being lower than expected. The study provides insights into key antenna parameters, such as the radiation pattern, the antenna’s quality factor, half-power bandwidth and effective height, as well as the radiated power level and the power lost through dissipation. This research presents the first documented numerical analysis of the Kootwijk VLF antenna and contributes to a better understanding of its historical performance. While the focus has been at VLF, this work can aid future modelling efforts for electrically small antennas at other frequency bands.

an image of our technical paper
The Radiation Resistance of Folded Antennas

This technical paper highlights the ambiguity in the antenna technical literature regarding the radiation resistance of folded antennas, such as the half-wave folded dipole (or quarter-wave folded monopole), electrically small self-resonant folded antennas and multiple-tuned antennas. The feed-point impedance of a folded antenna is increased over that of a single-element antenna but does this increase equate to an increase in the antenna’s radiation resistance or does the radiation resistance remain effectively the same and the increase in feed-point impedance is due to transformer action? Through theoretical analysis and numerical simulations, this study shows that the radiation resistance of a folded antenna is effectively the same as its single-element counterpart. This technical paper serves as an important point of clarification in the field of folded antennas. It also showcases Plextek's expertise in antenna theory and technologies. Practitioners in the antenna design field will find valuable information in this paper, contributing to a deeper understanding of folded antennas.

an image of our technical paper
Chilton Ionosonde Data & HF NVIS Predictions during Solar Cycle 23

This paper presents a comparison of Chilton ionosonde critical frequency measurements against vertical-incidence HF propagation predictions using ASAPS (Advanced Stand Alone Prediction System) and VOACAP (Voice of America Coverage Analysis Program). This analysis covers the time period from 1996 to 2010 (thereby covering solar cycle 23) and was carried out in the context of UK-centric near-vertical incidence skywave (NVIS) frequency predictions. Measured and predicted monthly median frequencies are compared, as are the upper and lower decile frequencies (10% and 90% respectively). The ASAPS basic MUF predictions generally agree with fxI (in lieu of fxF2) measurements, whereas those for VOACAP appear to be conservative for the Chilton ionosonde, particularly around solar maximum. Below ~4 MHz during winter nights around solar minimum, both ASAPS and VOACAP MUF predictions tend towards foF2, which is contrary to their underlying theory and requires further investigation. While VOACAP has greater errors at solar maximum, those for ASAPS increase at low or negative T-index values. Finally, VOACAP errors might be large when T-SSN exceeds ~15.

an image of our technical paper
Antenna GT Degradation with Inefficient Receive Antenna at HF

This paper presents the antenna G/T degradation incurred when communications systems use very inefficient receive antennas. This work is relevant when considering propagation predictions at HF (2-30 MHz), where it is commonly assumed that antennas are efficient/lossless and external noise dominates over internally generated noise at the receiver. Knowledge of the antenna G/T degradation enables correction of potentially optimistic HF predictions. Simple rules of-thumb are provided to identify scenarios when receive signal-to-noise ratios might be degraded.

an image of our technical paper
60 GHz F-Scan SIW Meanderline Antenna for Radar Applications

This paper describes the design and characterization of a frequency-scanning meanderline antenna for operation at 60 GHz. The design incorporates SIW techniques and slot radiating elements. The amplitude profile across the antenna aperture has been weighted to reduce sidelobe levels, which makes the design attractive for radar applications. Measured performance agrees with simulations, and the achieved beam profile and sidelobe levels are better than previously documented frequency-scanning designs at V and W bands.

an image of our technical paper
Midlatitude 5 MHz HF NVIS Links: Predictions vs. Measurements

Signal power measurements for a UK-based network of three beacon transmitters and five receiving stations operating on 5.290 MHz were taken over a 23 month period between May 2009 and March 2011, when solar flux levels were low. The median signal levels have been compared with monthly median signal level predictions generated using VOACAP (Voice of America Coverage Analysis Program) and ASAPS (Advanced Stand Alone Prediction System) HF prediction software with the emphasis on the near-vertical incidence sky wave (NVIS) links. Low RMS differences between measurements and predictions for September, October, November, and also March were observed. However, during the spring and summer months (April to August), greater RMS differences were observed that were not well predicted by VOACAP and ASAPS and are attributed to sporadic E and, possibly, deviative absorption influences. Similarly,the measurements showed greater attenuation than was predicted for December, January, and February, consistent with the anomalously high absorption associated with the “winter anomaly.” The summer RMS differences were generally lower for VOACAP than for ASAPS. Conversely, those for ASAPS were lower during the winter for the NVIS links considered in this analysis at the recent low point of the solar cycle. It remains to be seen whether or not these trends in predicted and measured signal levels on 5.290 MHz continue to be observed through the complete solar cycle.

an image of our technical paper
Electrically small monopoles: Classical vs. Self-Resonant

This paper shows that the Q-factor and VSWR of a monopole are significantly lowered when made resonant by reactive loading (as is used in practice). Comparison with a self-resonant Koch fractal monopole of equal height gives similar values of VSWR and Q-factor. Thus, the various electrically small monopoles (self-resonant and reactively loaded) offer comparable performance when ideal and lossless. However, in selecting the optimum design, conductor losses and mechanical construction at the frequency of interest must be considered. In essence, a trade-off is necessary to obtain an efficient, electrically small antenna suitable for the application in hand.

an image of our technical paper
Ku-Band Low-Sidelobe Waveguide Array

The design of a 16-element waveguide array employing radiating T-junctions that operates in the Ku band is described. Amplitude weighting results in low elevation sidelobe levels, while impedance matching provides a satisfactory VSWR, that are both achieved over a wide bandwidth (15.7-17.2 GHz). Simulation and measurement results, that agree very well, are presented. The design forms part of a 16 x 40 element waveguide array that achieves high gain and narrow beamwidths for use in an electronic-scanning radar system.