Communication Subsystems


The newest scientific missions from ESA require a consortium of so-called subsystem primes that are collaborating with the overall mission prime to develop the different subsystems (e.g. propulsion, payload, Communications…) of the Spacecraft.

Antwerp Space has been awarded with multiple contracts for the communication subsystems, due to the specific in-house expertise with complex RF technology and flight projects. Current projects are EXOMARS 2020 and JUICE, both deep space missions that will respectively target Mars and Jupiter.


EXOMARS (Exobiology on Mars)
Is a Space programme consisting of two missions to orbit around and land on Mars, executed in cooperation by ESA and Roscosmos, the Russian space agency. The first mission called ExoMars 2016, consisting of an orbiter and a lander, was launched on 14 March 2016 and arrived at Mars in October 2016. The second mission is scheduled for a launch in 2020. It includes a surface platform that will actually land on the planet and a rover that will explore the Martian surface

JUICE (JUpiter ICy moons Explorer)
is the first large-class mission in the European Space Agency’s (ESA) Cosmic Vision 2015-2025 programme. The JUICE spacecraft will provide a thorough investigation of the Jupiter system in all its complexity with emphasis on the three potentially ocean-bearing ‘Galilean’ moons: Ganymede, Europa and Callisto, and their potential habitability. It will be the first spacecraft ever to orbit a moon (Ganymede) of a giant planet.
The communication subsystem will enable the communication link with Earth during these missions. It includes basically a deep-space transponder, X- and if necessary Ka-band high power amplifiers (TWTAs) and a Radio Frequency Distribution Assembly (RFDA) that directs the signal towards the antennas. It can also incorporate several radio-science experiments if requested by the customer.
Antwerp Space is responsible for designing, integrating and testing these Communication Subsystem, before it is installed onto the spacecraft. The detailed design and manufacturing of the different units is subcontracted to different companies in Europe, under the capable supervision of Antwerp Space.
Thanks to these important contracts on major ESA missions, Antwerp Space is establishing itself as a trustful and reliable partner able to participate at a higher system level, and to handle the responsibilities that come with it.

Radioscience Transponder

Fast forward to 2021. Our Lander Radioscience (LaRa) is the first scientific instrument made in Belgium to ever land on the surface of Mars. It just had a long flight on board of the ExoMars 2020 mission. But nevertheless: it’s already starting its task to study the Red Planet’s rotation and core.


ExoMars: two missions to Mars    
Back to the present. ESA and the Russian space agency Roskomos are now working on the space programme ExoMars. Its two missions will orbit and land on Mars:
The first mission ExoMars 2016 – with an orbiter and a lander on board – was launched on 14 March 2016 and arrived in October 2016.
The second mission is scheduled for 2020. Its surface platform will actually land on the planet and a rover will explore the Martian surface.
 

A Belgian made instrument
The LaRa mission is designed by a scientific team from the Royal Observatory of Belgium in Brussels. Antwerp Space designs and delivers the instrument itself.
Several instruments are part of the scientific payload integrated in the surface platform. LaRa is one of two European ones. Russia supplies all the other instruments as well as the platform.


Mars: a raw or cooked egg?
The deep interior of a planet can be characterised by its rotation. Why? Because the planet’s rotation is influenced by the physical state of its interior. Compare it with a raw (liquid) egg that rotates differently than a cooked (solid) one. Therefore: the more scientists know about a planet’s rotation, the more they can learn about its core and its evolution.
And that’s where LaRa comes in. The LaRa instrument will receive a radio signal sent from Earth and beam it back from the Mars surface. First scientists analyse the characteristics of the radio signal received on Earth. Then they’re able to measure the planet’s rotation with an unprecedented accuracy, thus inferring the characteristics of its interior.
 


LaRa: our testimony of expertise
Overall, LaRa helps us understand the internal structure of Mars. And why Mars and the Earth did not evolve similarly. On top of that, the data gathered by LaRa allows us to investigate the influence of the redistribution of masses. For example: the migration of ice from the polar caps to the atmosphere and its impact on the rotation of Mars.
For Antwerp Space, LaRa marks the culmination of a period of fruitful cooperation with the team in charge at the Royal Observatory of Belgium. It is a testimony to the company’s heritage and expertise in the field of radio frequency.
The LaRa instrument is built thanks to the financial support of the PRODEX programme of ESA and with support of BELSPO.

Broadband Communication Modem

Spacecraft embark more computational power thanks to advances in electronics. And then mainly the rise of software-defined radio (SDR). As part of this new industry trend, Antwerp Space is developing a high-performance on-board processing platform.

We customize each product within the family by the development of mission-specific signal processing firmware and RF front-ends. The whole system is built around a highly integrated commercial SRAM FPGA.

Moreover, the data converters are based on the latest sub-sampling technology. Overall, this allows for roadmap flexibility and in-flight re-programmability (i.e. remote upgrade). The whole design is ITAR-unrestricted.
 


ARGO: communication between ISS and Earth
Its first application is ARGO, an advanced bi-directional modem. It will be used at the core of ColKa. This is a transponder ensuring the communication between the Columbus module of the International Space Station (ISS) and the Earth. Furthermore, all the communication runs through the European Data Relay System (EDRS).
ARGO provides a high-end interface to the data source. Because of its high computational power, it’s able to support the most demanding algorithms. For example: the CCSDS standard LDPS coding and encapsulation schemes. Or other features such as a complex antenna tracking function. It will be installed in 2018.
 

Key specifications
In this first implementation, the SDR unit is fully redundant. Despite this stringent requirement, it has relatively modest requirements. And it could easily be accommodated even on small satellite platforms. The key specifications are as follows:
  • Overall performance:
    • Downlink: 300 Mbps
    • Uplink: 2 Mbps
  • Mass: 3.6 kg
  • Volume: 3.8 L
  • Power consumption: 35 W
  • Life-time of 7.5 years

Endless applications
While the first model was planned as a modem, this versatility make it the ideal equipment for any operation with heavy computational requirements. Examples of such applications could include:
  • spectrum monitoring,
  • interference geo-localization,
  • image processing and compression for EO platforms,
  • space-based authentication payloads (AIS, VDE(S)),
  • or encryption of sensitive data.

Ka-Band Intersatellite equipment for Cubesat

Small satellite platforms are now extensively used for a wide variety of applications. The miniaturization of payloads enables operators to generate an ever-increasing amount of data. However, an important bottleneck remains with the communication system. To overcome this limitation, Antwerp Space NV is developing, in collaboration with the von Karman Institute, a Ka-band transceiver dedicated to small satellites.

With a very low mass, low volume, and low power consumption, it is easily accommodated on any spacecraft that requires inter-satellite communication. Its duty cycling capability allows to tailor the average data rate to the mission needs, thereby saving on power consumption.

The key specifications are as follows:

  • Overall performance: 1 Mbps over 4,300km
  • Presents itself as a set of 4 PCB boards:
  • Mass and volume smaller than 1U CubeSat
  • Solutions for localized shielding if required
  • Tunable power depending on data rate need:
  • 30W @ 100% duty cycle (1 Mbps) 19W @ 60% duty cycle (540 kbps)
  • Life-time of 3 years

This effort is conducted in the frame of the ARTES Advanced Technology program of ESA.
 


Flexible Ka-Band Regenerative Transponder

Small satellite platforms are now extensively used for a wide variety of applications. The miniaturization of payloads enables operators to generate an ever-increasing amount of data. However, an important bottleneck remains with the communication system. To overcome this limitation, Antwerp Space NV is developing, in collaboration with the von Karman Institute, a Ka-band transceiver dedicated to small satellites.

With a very low mass, low volume, and low power consumption, it is easily accommodated on any spacecraft that requires inter-satellite communication. Its duty cycling capability allows to tailor the average data rate to the mission needs, thereby saving on power consumption.

The key specifications are as follows:

  • Overall performance: 1 Mbps over 4,300km
  • Presents itself as a set of 4 PCB boards:
  • Mass and volume smaller than 1U CubeSat
  • Solutions for localized shielding if required
  • Tunable power depending on data rate need:
  • 30W @ 100% duty cycle (1 Mbps) 19W @ 60% duty cycle (540 kbps)
  • Life-time of 3 years

This effort is conducted in the frame of the ARTES Advanced Technology program of ESA.
 


Telecommand Telemetry & Control (TT&C)


Every spacecraft requires communication, both from an operational point of view (TT&C) and mission specific data from the payload itself. The Telemetry, Tracking and Command (TT&C) system is one of the mission-critical elements of a spacecraft. It allows the spacecraft to transmit its status information in terms of telemetry to the ground station; while allowing the ground station to transmit telecommands and perform ranging. On the other hand, the payload could generate a large amount of useful data that needs to be transferred to a ground station, sometimes referred to as payload data transmission (PDT).

To date, transponders are used for TT&C, and a separate communication subsystem is used for PDT. To minimize the customization and requalification effort that originates from the mission’s unique criticalities and specifications, an all-market, flexible and reconfigurable transponder would be an attractive alternative for current TT&C transponder solutions.
 


Payload Data Transmission (PDT)

In 2018, Antwerp Space was awarded a European Space Agency (ESA) contract to design a cutting-edge product family that exploits the flexibility and re-configurability to allow it to be used on almost all future ESA missions, with a particular focus on space research missions, earth observation satellites and navigation missions. Antwerp Space was given the extensive task to create a state-of-the-art product with unprecedented performance and flexibility.

Antwerp Space is well aware of the challenges to design such an all-mission profile product line, and took the approach of investing in the development of a hybrid (hardware-software) simulation platform that is intended to be used regularly even once production of the Flight Models are launched. This platform enables to support early estimations of mission specific changes in support of Equipment Qualification Status Reviews as well as early compatibility testing with ground assets.
As part of the innovations in the current baseline, forward error correction schemes can be implemented in the transponder, a deep sleep listening mode enables very low standby power consumption levels, and PDT functions in multiple bands are available as hardware extensions.

Antwerp Space is currently collecting feedback on their requirements and architectural design. We invite the interested readers to give feedback on our approach. In the next months, further elaboration and verification on the software simulator will be performed. Additionally, some of the building blocks will be evaluated in a hardware Elegant Bread Board. Moreover, Antwerp Space will proceed towards its next milestones to demonstrate their innovative TT&C transponder with PDT, paving the way towards a next-generation of innovative flight equipment.

Applications:

  • Space Research
  • Earth Observations (Earth Exploration Services)
  • Category A missions (LEO, MEO, GEO, Cubesat, Lagrange 2, …)
  • Category B missions (Deep-Space, Mars, …)
  • Navigation (Space Operation Services)
     

Integrated TT&C and PDT


Antwerp Space plays a prominent role in the design and delivery of the deep-space communication subsystems for the Exomars 2020 and Juice missions. Nowadays Europe depends too much on a single provider for deep space transponder equipment. In order to overcome that, ESA has awarded a contract to Antwerp Space to develop a next-generation highly flexible transponder equipment that can serve as a second source and will be suitable for almost all science missions.

This state-of-the-art transponder will be developed using a modular approach, compatible with almost all future space research and earth observation missions for both TT&C and payload data transmission. The latest advances in software-defined radio will be combined with cutting-edge technologies, the newest modulation schemes and next-generation integrated circuits to support this breakthrough flight equipment.

The award of this contract recognizes Antwerp Space’s innovation initiatives and proves ESA’s trust in delivering flight equipment for ESA flagship missions and builds on the success of the LARA coherent transponder and the recently delivered ARGO modem.

Telemetry, Tracking & Command System

Every spacecraft requires communication, both from an operational point of view (TT&C) and mission specific data from the payload itself. The Telemetry, Tracking and Command (TT&C) system is one of the mission-critical elements of a spacecraft. It allows the spacecraft to transmit its status information in terms of telemetry to the ground station; while allowing the ground station to transmit telecommands and perform ranging. On the other hand, the payload could generate a large amount of useful data that needs to be transferred to a ground station, sometimes referred to as payload data transmission (PDT).

To date, transponders are used for TT&C, and a separate communication subsystem is used for PDT. To minimize the customization and requalification effort that originates from the mission’s unique criticalities and specifications, an all-market, flexible and reconfigurable transponder would be an attractive alternative for current TT&C transponder solutions.

And this is where we come in...

In 2018, Antwerp Space was awarded a European Space Agency (ESA) contract to design a cutting-edge product family that exploits the flexibility and re-configurability to allow it to be used on almost all future ESA missions, with a particular focus on space research missions, earth observation satellites and navigation missions. Antwerp Space was given the extensive task to create a state-of-the-art product with unprecedented performance and flexibility.

Antwerp Space is well aware of the challenges to design such an all-mission profile product line, and took the approach of investing in the development of a hybrid (hardware-software) simulation platform that is intended to be used regularly even once production of the Flight Models are launched. This platform enables to support early estimations of mission specific changes in support of Equipment Qualification Status Reviews as well as early compatibility testing with ground assets.

As part of the innovations in the current baseline, forward error correction schemes can be implemented in the transponder, a deep sleep listening mode enables very low standby power consumption levels, and PDT functions in multiple bands are available as hardware extensions.

Antwerp Space is currently collecting feedback on their requirements and architectural design. We invite the interested readers to give feedback on our approach. In the next months, further elaboration and verification on the software simulator will be performed. Additionally, some of the building blocks will be evaluated in a hardware Elegant Bread Board. Moreover, Antwerp Space will proceed towards its next milestones to demonstrate their innovative TT&C transponder with PDT, paving the way towards a next-generation of innovative flight equipment.

Applications

  • Space Research
  • Earth Observations (Earth Exploration Services)
  • Category A missions (LEO, MEO, GEO, Cubesat, Lagrange 2, …)
  • Category B missions (Deep-Space, Mars, …)
  • Navigation (Space Operation Services)