Towards Standardised RF Inter-Satellite Link Solutions Towards Standardised RF Inter-Satellite Link Solutions

  • Status
  • Status date
  • Activity Code

The objectives of the project are as follows:

  1. Explore the definition of a set of consolidated RF ISL system architectures that are applicable for a range of mission scenarios taking into account various system topologies, design principles and qualification requirements.

  2. Define baseline system, sub-system, and equipment specification envelopes based on size, weight, power and minimum performance requirements applicable to the most common mission scenarios.

  3. Explore the limits of establishing commonality in the physical and digital interfaces of the various system elements and seek to promote design reusability throughout the value chain.

  4. Propose a baseline (First Issue) Standardised RF ISL System Framework, clearly identifying its scope, objectives, and contents to enable system designers and equipment manufacturers to specify and design against a common set of system, sub-system, and equipment requirements

  5. Define a governance structure to ensure the Framework is manageable, stays relevant, and delivers its intended objectives, and also includes the means to encourage and facilitate continuous improvement.

  6. Propose an implementation plan for the Framework and recommend follow on activities.


The key challenges of the project fundamentally relate to the breadth of use cases for inter-satellite links, ranging from low-cost nanosatellite constellations to high reliability deep space network nodes.

The aim of this project is to develop a framework to allow standardisation of this broad spectrum without severely compromising use cases or performance for any particular application or mission.


The output of this project provides a framework to define and describe inter-satellite link subsystems to promote inter-operation and technology re-use.

There is currently no recognised standardisation for RF inter-satellite links, which has led to a wide range of non-interchangeable proprietary solutions being offered by a range of manufacturers.

This framework will foster competition and provide flexibility for satellite integrators to specify an inter-satellite link function without being bound to a specific proprietary solution.


The product consists of the following:

  • Standardised RF ISL System Framework

  • Implementation and Governance Strategy

System Architecture

The framework uses a generic modular inter-satellite link communications system as the baseline for defining subsystems and elements. This is intended to allow interchangeability between elements of the system (e.g. antennas, amplifiers, baseband).


The project consists of 2 key phases.

In the first phase existing technologies, frameworks and mission requirements for inter-satellite links are explored and captured. These requirements are then analysed and used to generate a baseline architectural definition for an inter-satellite link product alongside an outline structure and content for the framework itself.

The second phase of the project uses the inputs from the first phase to generate an initial draft of the framework, alongside management constraints with respect to technical review, governance and lifecycle. The framework is shared with industry and updated based on feedback.

Current status

The project has concluded its research into current and future use of ISL technologies and analysis of other industry leading frameworks.

The analysis concluded that an industry led, ESA backed, framework based upon best of industry knowledge would be a suitable mechanisms to lead towards standardisation of RF ISL Systems. A proposed framework was drafted along with an implementation strategy and after initial industry engagement there is initial interest to drive the framework forward.

Prime Contractor