Objectives

Quantum computing promises to revolutionise a number of fields by solving certain computational tasks faster than what can be achieved with classical computers. To fully achieve this ambitious promise, it is crucial to interconnect Quantum Processing Units (QPUs) in order to run algorithms cooperatively in a distributed fashion, tackling problems beyond the capability of a single QPU and thus enabling a whole new range of applications and use cases. In this context, a paramount problem is how to efficiently distribute entanglement over large distances in order to interconnect faraway QPU. In this project, we are going to study architectures for distributed quantum computing (DQC) enabled by space connectivity. To this aim, we will survey different use cases, quantum algorithms and their suitability for parallelization. We will also address different qubit platforms and other relevant components, such as entangled photon sources, transducers, and quantum memories. We will run extensive simulations collecting all these ingredients together to identify an architecture supporting as many use cases as possible and to formulate a technology roadmap for future developments.

Challenges

• Identification of use cases where a distributed quantum algorithm outperforms a classical solution.
• Identification of the quantum algorithms more suitable for parallelisation and investigation of the distributed compiler performance.
• Identification of the best qubit platform(s) allowing for long-distance interconnection via entanglement distribution.
• Propose practical architectures to run distributed quantum algorithms. This architecture shall be able to perform non-local two-qubit gate operations that will be required to distribute the computation among different QPU.
• Identification of the most promising components, whose development will enable the successful realisation of as many use cases as possible.

Plan

• Use cases, and reference scenario definition
• Technical Specification
• Optimal Technical Baseline Identification
• Technology Assessment and Development Plan

Current Status

We have initiated the survey part of the project. In particular, on the software side, we are reviewing the currently available use cases, with the algorithms more suitable for parallelisation and the distributed quantum compiler. On the hardware side, we are investigating the qubit platform, the transducers, and the quantum memory.

We are also kick-starting the simulation activities for the distribution of entangled photons from satellites, evaluating rates and fidelities.

Companies

TNO

https://www.tno.nl/en

The Netherlands

Objectives

The project aims to design, specify, and validate compact optical modules critical for spaceborne quantum key distribution (QKD) systems. Key objectives include setting the preliminary design, finalizing technical specifications, confirming the detailed design, and defining relevant environmental conditions for prototype validation and functional testing. The focus lies on developing space-compatible Entangled Photon Sources (EPS) and Faint Pulse Sources (FPS), optimizing for Size, Weight, Power, and Cost (SWaP-C). Particular attention is given to balancing EPS unit size and photon pair brightness by adjusting the length and form of the periodically poled potassium titanyl phosphate (ppKTP) crystal. This approach enables the possibility of using multiple compact EPS units on a single satellite to improve performance and redundancy.

Challenges

A key challenge of the project lies in ultimate miniaturisation of single photon sources in order to showcase them in practical QKD applications.

System Architecture

The EPS employs a high-power (>100 mW) SLM pump laser at 405 nm and uses periodically poled nonlinear crystals, for efficient spontaneous parametric down-conversion. Robotic manipulators are used to position and bond small optical components (≤3 mm), ensuring precise alignment. Critical to performance are stable thermoelectric cooling (±0.001 K), high-fidelity entanglement generation, and reliable polarization-maintaining fibre coupling with high polarization extinction ratio and angular stability. The FPS utilises compact, switched gain-chips and a common seed to emit pulses at up to 1 GHz with stable amplitude and precise timing. A two-channel switching driver controls emission. Similar robotic optical assembly techniques are applied to align and bond small optical components, ensuring consistent PM fibre coupling. Both modules use commercial off-the-shelf components and robust assembly methods, supporting potential space qualification. The overall architecture reflects a high degree of integration and precision, enabling stable and scalable photon generation for quantum key distribution applications.

Plan

The project follows a structured plan divided into key phases: initial requirements analysis, preliminary and detailed design, component procurement and assembly, and functional testing. Major milestones include a meeting to define the characterization strategy, a Preliminary Design Review, a Test Readiness Review, and a Critical Design Review. The project concludes with a final presentation to ESA.

Current Status

The project has progressed from concept development toward prototype definition. Detailed technical specifications for key components have been initiated based on system requirements. A market survey identified suitable EU-based suppliers, and initial orders have been placed. A literature review of electrical and fluid power systems is ongoing to support design decisions. Risk identification and mitigation planning have also begun.

Companies

Integrated Optics, UAB

https://integratedoptics.com/

Objectives

The AutoMAIT project focuses on creating automated processes for attaching micro-optic to photonic integrated circuits (PICs) aimed at satellite applications. Objectives include enhancing assembly reliability and repeatability, improving optical coupling efficiency, reducing manual degrees of freedom, and developing processes that withstand harsh environmental conditions like thermal cycling and vibration. The project advances these packaging processes to a technology readiness level (TRL5), enabling high-volume manufacturing for the price-sensitive Non-Geostationary Orbit (NGSO) market and supporting MBRYONICS’ STARCOM and TeraBIX product lines.

Challenges

The AutoMAIT project encompasses challenges in developing automated micro-optic attachment processes for photonic integrated circuits. Key issues include achieving reliable and repeatable assembly, reducing the degrees of freedom in current processes, and improving optical coupling efficiency. Ensuring the processes and components could withstand harsh environmental conditions, like thermal cycling and vibration, was also a significant hurdle. The report also discusses the need for future production automation to meet market demands.

System Architecture

The AutoMAIT system focuses on automating the micro-optic attachment process for photonic integrated circuits (PICs) used in satellite applications. The core of the system revolves around a Finetech Lambda 2 flip-chip bonder, which provides precise placement and alignment capabilities. This bonder is enhanced with custom-designed fixtures for thermal bonding and environmental testing.

The architecture includes automated epoxy dispensing for controlled application of adhesive. Optical feedback mechanisms are integrated for real-time monitoring and optimization of optical coupling during the alignment process. Specifically designed PICs, lensed fibre arrays, and various epoxy types are key components. The system undergoes rigorous post-process testing, including die shear, mechanical shock and vibration, thermal cycling, and TVAC (thermal vacuum) testing to ensure reliability in harsh space environments.

Plan

The AutoMAIT project phases include developing flip-chip based micro-lens and fibre array attachment processes for photonic integrated circuits. Key milestones involve design considerations for reduced degrees of freedom in optical alignment, automated epoxy deposition, and curing processes. Post-process testing was conducted, including die shear, mechanical shock and vibration, thermal cycling, and TVAC testing to evaluate the processes’ effectiveness and environmental resilience for satellite applications. Additionally, the project included roadmapping and business development strategies for future automation and market engagement.

Current Status

The AutoMAIT project has developed and tested automated photonic packaging processes for satellite communications, focusing on improving optical coupling efficiency and reliability for high-volume manufacturing. Testing, including die shear, mechanical shock, vibration, thermal cycling, and TVAC, has been completed. The report also outlines future roadmapping and business development strategies, including plans for production automation, market analysis, and customer engagement, with a focus on supporting MBRYONICS’ STARCOM and TeraBIX product lines.

Related Links

• MBRYONICS, Ltd.

Objectives

The OPTIMUS test bench establishes a foundation for next-generation optical communication services by demonstrating robust, user-driven capabilities in scheduling, data delivery, and network monitoring. It enables seamless registration of OGS, Network Operations Centers (NOCs), and satellite operators via a lightweight, harmonised process that ensures interoperability across diverse optical systems. By implementing a “NOC of NOCs” architecture, OPTIMUS centralises planning and resource management to maximise pass reliability and data throughput. The platform integrates Human-Machine Interface, planning algorithms, real-time monitoring, and networking modules into a cohesive framework, supporting both single- and multi-OGS scenarios under realistic operational conditions.

OPTIMUS also serves as a reference for standardisation and can host advanced use cases such as quantum key distribution and quantum communication experiments. Through rigorous requirement refinement, design finalisation, and targeted validation tests, the project raises the solution’s Technology Readiness Level and prepares it for seamless integration into operational environments – laying the groundwork for scalable, cost-effective Optical Communications as a Service.

Challenges

The project navigates three key challenges: integrating a still-maturing Disruption Tolerant Networking (DTN) protocol end-to-end – requiring protocol conversion and satellite-simulator support; coordinating diverse subsystems (planning, HMI, DTN, HCC, monitoring) developed by multiple teams using agile methods and clear workflows; and balancing cost-driven design constraints by leveraging open-source software, consortium expertise, and careful trade-offs to contain development, licensing, and integration expenses.

System Architecture

The Testbed adopts a modular, service-oriented architecture comprising five key components interconnected by secure, standardised interfaces:

• Human-Machine Interface (HMI) serves as the entry point for operators and customers, providing registration, scheduling, simulation control, and data retrieval.
• Scheduler & Optimisation Engine processes pass requests, applies link-budget and cost-based ranking, and handles dynamic rescheduling. It exposes REST endpoints and publishes scheduling events to an internal message bus.
• Holistic Control Centre (HCC) serves as a middleware as it provides within OPTIMUS the ability to dynamically connect OGS or OGS-networks. OGSs can connect to the entire system as new services and HCC provides the needed infrastructure to provide coherent configurations, security and so on.
• Emulator consumes scheduling events to drive spacecraft-to-ground interaction scenarios under configurable impairments (latency, packet loss, handover), streaming telemetry results to the monitoring layer.
• Central Monitoring System (CMS) subscribes to health and performance topics on the message bus, aggregates metrics in a time-series database, and pushes alerts and trend data to the HMI.

A DTN integration layer underlies data transfers, segmenting and forwarding bundles over intermittent links. The architecture enables independent development, easy scalability to multiple operators, and robust validation of optical communication workflows.

Plan

The project unfolds in five phases, each ending with a formal milestone review:

1. Preparation – Project Kick-Off (KO) and State-of-the-Art/Trade-Off studies, concluding with the Preliminary Design Review (PDR).
2. Design – Architecture and ICD alignment, ending at the Critical Design Review (CDR).
3. Build – Module implementation and system integration, culminating in the Factory Test Readiness Review (FTRR).
4. Test – System and interface validations (including remote OGS), fixes applied, ready for the Test Readiness Review (TRR).
5. Operate – Operational demonstrations and final handover at the Final Review (FR).

Current Status

The project is in the Preparation phase, having completed the Kick-Off and initiated State-of-the-Art studies and technology trade-off analyses. Core activities include defining detailed user scenarios, refining high-level requirements, and setting up development environments. Upcoming tasks focus on finalising the Preliminary Design Review inputs, solidifying the ICD framework, and aligning stakeholder workflows to ensure a smooth transition into the Design phase.

Companies

DLR Gesellschaft für Raumfahrtanwendungen mbH (DLR GfR mbH)

https://www.dlr-gfr.com

Germany

DLR Space Operations and Astronaut Training (DLR/RB)

https://www.dlr.de/en/rb

Germany

Swedish Space Corporation

https://sscspace.com

Sweden

IP Camp

https://ip-camp.com

Hungary

Objectives

The primary objective of this project is to design, fabricate, and characterize a 2.5 Gbps APD receiver, aiming for a fivefold improvement in sensitivity compared to commercially avaliable InGaAs APDs. Additionally, the project includes the development of APD chips with bandwidths of 200 MHz, 500 MHz, and 1 GHz. These APD chips are designed for operation at a 1550 nm wavelength, featuring low noise, high responsivity, and minimal dark current.

The receiver integrates APD chips developed by Albis, along with commercially available off-the-shelf (COTS) passive components and a radiation-hard transimpedance amplifier (TIA). Furthermore, the project includes the development of an evaluation board to facilitate straightforward testing of the receiver’s functionality in a laboratory setting.

Challenges

To achieve the targeted 5-fold sensitivity improvement in the AO-LIMA project, the main APD design requirements include:

• High unity gain responsivity to enable high signal amplitude at all multiplication gains.
• Low k-ratio (i.e. low excess noise factor) to reduce APD and receiver NEP, and improves receiver sensitivity.
• Operation at high multiplication gain to achieve the improved sensitivity with low k-material.
• Large gain-bandwidth product to allow for high data rate transmission at high multiplication gain.
• Low APD dark current to reduce APD NEP.

The key challenge is to find an optimum balance between the APD noise and the operational gain.

System Architecture

The following product tree is a hierarchical breakdown of the product into the hardware and software elements:

The key products or elements are described below:

APD Chip

The avalanche photodiode (APD) chip serves as the optical signal detector, converting incoming optical signals into electrical output. Leveraging a low-noise avalanche multiplication process, the APD chip provides significant internal gain with minimal excess noise, achieving at least a fivefold improvement in detection sensitivity compared to existing InGaAs APDs at 2.5 Gbps. The chip features a large active region with an anti-reflective coating on the front side to enable efficient optical coupling to a 50 µm multimode fiber at a 1550 nm wavelength.
 

Readout Electronics

The readout circuit amplifies the RF electrical signal generated by the APD and delivers a differential data output pair. Additionally, if required, it can provide a discretized digital signal, enabling a hard decision output (“0” or “1”).
 

Evaluation Board

The evaluation board is designed to facilitate performance assessment of the receiver. It includes all necessary connections for biasing and signal readout, ensuring ease of use in laboratory testing environments.

Plan

The project consists of two development phases: a “Technology-preparation” and a “Technology – development” phase. In the preparation part we conduct literature study to review the state-of-the-art, propose preliminary device design and run simulations. The development phase includes two rounds of APD manufacturing and testing. The first round is to design development test structures to validate the models, verify the compliance with the SoW requirements, and to define the final design. The second round manufactures the final APDs and the receivers, and performs thorough compliance verification testing including radiation testing. Finally, a global analysis of the results is performed.

Current Status

The project started with a Kick-Off-Meeting in March 2025. The project is currently in the “Technology – preparation” phase.

Albis team concludes an assessment of the current state-of-the-art InGaAs APD and is diving deeply into the simulation models. Albis team is actively engaged in brainstorming sessions to create an innovative and optimal device design that can accommodate the demanding technical requirements of AO-LIMA project.

Companies

Albis Optoelectronics AG

http://www.albisopto.com

Switzerland