ISS-COLKa (Columbus Ka-band antenna)
MDA (MacDonald Dettwiler and Associates Ltd.), a Maxar Technologies company, today announced that technology developed by its UK division in partnership with the UK Space Agency and the Canadian Space Agency has begun its journey to the ISS (International Space Station). The COLKa terminal of ESA (European Space Agency) was launched on 15 February 2020 aboard the Cygnus NG-13 Commercial Resupply Mission to the ISS. 1)
The MDA-built terminal will complement existing communication systems on board the ISS and utilize the EDRS (European Data Relay Satellite). Operating in the Ka-band, COLKa will enable dramatically higher communications bandwidth between ESA's Columbus laboratory module on the ISS and ground stations and will provide ESA with an independent connection for faster delivery of scientific data and high-definition video. As a result, UK and European scientists and researchers will be able to see results of their ISS science experiments almost instantaneously.
COLKa was designed, developed and integrated by MDA Space and Robotics Limited in the UK, using funding provided by the UK Space Agency through the ESA Human Spaceflight program, the Canadian Space Agency through its cooperation agreement with the ESA, through the ESA ARTES program as well as through internal investment. MDA was supported on the project by Kongsberg Defence and Aerospace of Norway and Antwerp Space of Belgium, both of which made significant contributions to the development of key subsystems.
"This is the first major industrial contribution from the UK to the ISS, and it will revolutionize the ability of scientists in the UK and Europe to access the results of their experiments," said Dr Graham Turnock, CEO of the UK Space Agency. "This is yet another example of the UK economy benefiting, through investment, jobs and new skills, from our continued collaboration with the European Space Agency."
"The COLKa program has firmly established MDA in the UK as a leading provider of high-quality space equipment, positioning us for continued business growth and new jobs in both communications and space sensor markets," said David Kenyon, Managing Director of MDA Space and Robotics Limited in the UK.
Developed with ARTES funding for some units, this fridge-sized telecom system was designed and built by UK (MDA) and Italian (Kayser Italia) companies as prime contractors, using products from Norway (Konsberg), Belgium (Antwerp Space), France (Thales Alenia Space), Canada (MDA) and Germany [ASP (Advanced Space Power Equipment GmbH) of Salem, Lake Constance].
The upgrade to the ESA Columbus laboratory will relay data from experiments on the Station back to Earth almost instantaneously. The device will send signals from the Station, which orbits at an altitude of 400 km above Earth, even further into space, where they will be picked up by EDRS satellites in geostationary orbit 36,000 km above the surface. 2)
Figure 1: Astronauts aboard the ISS plan to install a high-speed radio link to enable almost real-time connections with Earth. This image of the Columbus module was taken by ESA astronaut Luca Parmitano from outside the ISS on the second spacewalk to service the cosmic ray detecting Alpha Magnetic Spectrometer (AMS-02) on November 22, 2019 (image credit: ESA)
Launch: The Cygnus NG-13 spacecraft was launched on 15 February 2020 (20:21 GMT) on an Antares 230+ rocket from Virginia Space's MARS (Mid-Atlantic Regional Spaceport) at NASA's Wallops Flight Facility. This was Northrop Grumman's 13th commercial resupply NASA-contracted mission. Cygnus was loaded with more the 3,630 kg of research, crew supplies and hardware. — The COLKa instrument was part of the equipment on this flight. 3)
Orbit: Near circular orbit, altitude of ~ 400 km, inclination = 51.6º, period of~92 minutes.
After the capture of Cygnus NG-13 at the ISS on February 18, 2020, the Northrop Grumman Cygnus spacecraft was bolted into place on the International Space Station's Earth-facing port of the Unity module. 4)
COLKa instrument and development status
The COLKa Terminal will provide bi-directional communications between the Columbus laboratory and the EDRS satellite communication system. It is made up of a steerable antenna, RF signal processing assemblies (LNAs, frequency converters, etc.), digital signal processing assemblies (digital modulators and digital demodulators), Command and Data Handling assemblies (PIAU), DC power conditioning assemblies (PDU), micro-wave filters, waveguides inter-connects, co-axial cable inter-connects, high speed digital cable inter-connects as well as of survival heaters and DC harnesses. With the Forward Service Link , low-rate data is relayed from the EDRS System Ground Segment to the COLKa Terminal via the EDRS GEO satellite. The Return Service Link, also via the COLKa Terminal to the EDRS Ground segment via the EDRS GEO satellite, provides high-rate user data communications between the COLKa Terminal and the EDRS Ground Segment, such as video, sensor data, etc. 5)
The COLKa Terminal, along with the COLKa Platform, is identified as the COLKa Flight Unit (FU). The COLKa FU will be installed on a pre-defined, external section of the ISS Columbus Platform. The COLKa FU will be connected to Columbus laboratory interfaces via six cable harnesses. Delivered by the Embarkation Contractor (i.e. KI), the COLKa Platform includes the support panels and structure designed to withstand thermal and structural environments, interfacing with the COLKa Terminal equipment, the Columbus laboratory and the launch vehicle/temporary on-orbit stowage location. It also provides radiation shielding and protection against space debris and micrometeorites for the installed Terminal equipment.
Thermal design: The COLKa FU thermal control is based on heat dissipation through thermal radiative surfaces to limit higher temperatures in hot cases and the use of heaters to limit lower temperatures in the cold cases. Thermal insulating blankets, made of MLI, cover the non-radiative surfaces so to limit the heat rejection towards Columbus and the other ISS elements and so to contribute at limiting the COLKa FU temperature variations.
The outer layer of the MLI blanket will be made of a UV radiation and atomic oxygen resistant outer layer (Beta Cloth). The conductive heat flow, towards the Columbus through the Attachment feet and Attachment Bolts, is limited by using thermally insulating washers between the Attachment Bolts Stud and the Attachment Feet and between the Attachment Feet and the Columbus MDPS panels.
Figure 2: The COLKa antenna is being tested in the Hertz Test Chamber of ESA/ESTEC (image credit: ESA, M. Cowan) 6)
The COLKa system promises speeds of up to 50 Mbit/s in downlink and up to 2 Mbit/s in uplink. This will allow astronauts and researchers to benefit from a direct link with Europe at home broadband speeds – delivering a whole family's worth of high data volume downlink and video streaming for science and communications.
The EDRS (European Data Relay Satellite) will transmit the data to a ground station at Harwell, UK, near ESA's (European Center for Space Applications and Telecommunications), and from there the data will be transferred to the Columbus Control Center at DLR(Oberpfaffenhofen) and to user centers across Europe.
Kongsberg has been part of the team developing the terminal, through its Space & Surveillance division's environment in Horten, Norway. The project has been headed by MDA Space and Robotics Limited, the UK division of MDA, the world leading Canadian space equipment manufacturer. 7)
Our Space Electronics team in Horten, formerly known as Norspace, has developed, manufactured and delivered frequency converters. They are critical parts of the COLKa Ka-band ISL (Inter-Satellite Link) terminal provided by MDA. The terminal itself offers the astronauts greater capacity and availability of broadband connection, as it is capable of speeds of up to 400 Mbit/s downlink and 50 Mbit/s uplink, says Ellen Tuset, Vice President Division Space in Kongsberg.
Figure 3: Kongsberg has delivered frequency converters to the COLKa terminal (image credit: Kongsberg)
Advanced ARGO modem of Antwerp Space for COLKa 8)
The advanced ARGO modem, developed by Antwerp Space, uses a high-performing encoding technology for the very first time in Europe. This modem will enable faster communication from the ISS to Earth via the new European Data Relay Satellite System (EDRS). The innovative Field Programmable Gate Array (FPGA)-based design allows an in-flight reconfiguration of the modem and gives a higher flexibility for different communication demands. The modem has been integrated within the MDA Corporation Ka-band Data Relay terminal COLKa, that will be mounted on the ESA Columbus module of the ISS in April.
ARGO is a bidirectional SDR (Software Defined Radio) modem, a transponder ensuring the the communication between the Columbus module of the ISS (International Space Station) and the Earth via EDRS (European Data Relay System). Because of its high computational power, ARGO is able to support the most demanding algorithms.
Figure 4: Photo of the ARGO modem (image credit: Antwerp Space)
Features of ARGO: 9)
The data relay modem has an RF interface in L-band. The modulator features downlink data rates up to 300 Mbit/s using O/QPSK modulation with a TX bandwidth of 405 MHz, while the demodulator features uplink data rates up to 2 Mbit/s using QPSK modulation with an RX bandwidth of 4 MHz. All CCSDS standard LDPC coding schemes and encapsulation schemes can be supported. The modem also supports high-gain antenna tracking functions.
The high level of FPGA integration is first an enabler for powerful and demanding algorithms: advanced coding layers (LDPC, Turbo-codes), spectral monitoring, authentication and encryption, as well as unified digital architectures such as putting all demodulator and modulator functions in one equipment. Also the SEU protection mechanisms are a lot more flexible in terms of cost to the customer. On top of those key advantages, the power-to-function ratio scales according to the level of integration, which can be used to fit demanding algorithms in challenging power envelopes.
To leverage this digital flexibility, and enable new applications without requiring a redesign in the digital hardware part of the system, it is organized so that only a redesign of the RF part is necessary. This RF section itself contributes to overall flexibility, being designed around subsampling data converters.
Another asset of this product is its in-flight reprogrammability as driven by market demand. Based on the fact that the SRAM-based FPGA is natively reprogrammable because of its need to be loaded at each boot time, Antwerp Space developed reliable upgrade procedures.
System architecture: The equipment is designed to be powered from a 28 V bus with a maximum power consumption of 35 W. For a cold redundant unit the mass budget is 3.6 kg, and the volume budget is 3.8 liter.
The equipment is divided into primary power supply conditioning done in the PSU board, RF signal processing functions and digital processing functions.
Installation and Status of ColKa
• March 16, 2021: The ColKa and Bartolomeo facilities outside ESA's space laboratory Columbus taken during their installation spacewalk on 27 January 2021. 10)
Figure 5: Photo of the ColKa and Bartolomeo facilities outside ESA's space laboratory Columbus taken on 27 January 2021 (image credit: ESA/NASA)
• March 10, 2021: An orange pouch and a yellow cable are paving the way for missions to the Moon. By monitoring space radiation and enabling faster communications, the Dosis-3D experiment and the ColKa (Columbus Ka-band ) terminal, respectively, are providing the insights needed to enable safer missions father out in space. 11)
Figure 6: Orange Dosis-3D pouches are everywhere in the Columbus laboratory on the International Space Station. A series of active and passive dosimeters, they measure space radiation inside the module as well as how it penetrates the Space Station's walls (image credit: ESA/NASA)
- Radiation levels in space are up to 15 times higher than on Earth. As soon as humans leave the protective shield that is Earth's atmosphere, space radiation becomes a serious concern.
- The Columbus module is monitored by 11 passive dosimeters. The dosimeters are about the size of a pack of playing cards and attach to the walls of Columbus with Velcro. The detectors record how much radiation has been absorbed in total during the period they are in space.
- This experiment has been monitoring radiation levels for a number of years and after each six-month crew rotation, the detectors are replaced to record changes in radiation.
- In addition to the passive detectors, Dosis-3D uses active dosimeters that measure fluctuations in radiation levels over time. Data from all Station partners is shared to create as complete a picture of space radiation as possible.
- Dosimeters will also be flown on the Gateway, the next human habitat to be built in the vicinity of the Moon, to generate a more accurate assessment of radiation in lunar orbit.
- Meanwhile, the ColKa communications terminal visible in this image, will connect the Columbus module to the European Data Relay System satellites in geostationary orbit that transfer data via European ground stations. ColKa was installed during a recent spacewalk and began commissioning this week. It will enable faster uplink and downlink speeds between the European segment of the Space Station and European researchers on the ground.
- The know-how gained from designing, building and running ColKa could potentially be used in exploring farther from Earth in the Gateway around the Moon. ESA will supply the ESPRIT module for communications, scientific experiments, and refuelling for the international lunar outpost.
- These ambitious plans require reliable navigation and telecommunication capabilities to succeed. Building these independently would be costly, complex and inefficient.
- If this work were outsourced to a consortium of space companies that could put a constellation of satellites around the Moon, each individual mission would become more cost-efficient.
- As part of an initiative called Moonlight, ESA is now conducting deep analyses of the planned lunar missions and further developing possible solutions, both technical and business-related, to provide telecommunications and navigation services for the Moon.
• February 2, 2021: Spacewalkers are in constant contact with just one person during a spacewalk. This ‘ground IV' is a fellow astronaut who is experienced with every procedure of a particular spacewalk. 12)
- In preparation to guide Mike and Victor through this spacewalk, Andreas previously performed practice runs of the European Columbus KA-band antenna ColKa's installation at the Neutral Buoyancy Lab – a pool sporting life-sized mock-ups of the International Space Station.
Figure 7: A peak into NASA's Mission Control in Houston: what looks like a coffee break is actually ESA astronaut Andreas Mogensen (centre) hard at work, guiding NASA astronauts Mike Hopkins and Victor Glover via radio during last week's spacewalk (image credit: ESA)
- The spacewalk started well. The fridge-sized unit was transported by Victor from the airlock to the worksite on the Canadarm2 robotic arm. There, the spacewalking duo set to work unscrewing and screwing bolts to hold the antenna in place and routing cables for power and data. However, despite seemingly secure connections, the heaters did not activate as expected.
- Serving as the interface between the European ground crews and the astronauts, Andreas relayed the situation in space and the solution from ground: remove and jettison the cover. With ColKa's temporary protective cover safely cast away to burn up in Earth's atmosphere, the temperature dropped and ColKa's heaters activated. Everyone breathed a sigh of relief as they reported the antenna safely installed.
- Once fully operational, ColKa will create an additional bi-directional KA-band data transmission for the Space Station, providing a direct link between the Columbus laboratory and Europe, for researchers and astronauts, at home broadband speeds.
- Teams at Columbus Control Centre will be carrying out tests this month to ensure it is fully operational. Once all is up and running, ColKa will use the use the European Data Relay System (EDRS) – dubbed the ‘SpaceDataHighway' – to relay data directly between the Station and European soil via the system's ground station in Harwell, UK.
- ColKa was not the only European facility keeping astronauts busy on Wednesday. Mike and Victor were also tasked with connecting power and data cables for exterior commercial research platform Bartolomeo.
- In this case, the spacewalkers were not able to connect all the required power cables between the platform and Columbus. This task will be tackled in a future spacewalk.
- Read more details about the spacewalk in this blog post.
• January 27, 2021: Two astronauts working outside the International Space Station Wednesday installed a European Space Agency data relay antenna and connected four of six cables to partially power a new ESA experiment platform. They also removed two solar array handling fixtures to clear the way for a future power system upgrade. 13)
- But the two cables they were unable to connect to the Bartolomeo platform, attached to the front side of ESA's Columbus laboratory module, will need to be connected later to accommodate a full suite of external payloads.
Figure 8: Astronaut Mike Hopkins makes his way to a worksite on the European Space Agency's Columbus laboratory module where he and fellow spacewalker Victor Glover plan to attach a new data relay antenna. The astronauts also plan to connect power and data cables to a European experiment platform and make preparations for future solar array upgrades (image credit: NASA TV)
- "At least we got partially connected to Bartolomeo," European astronaut Andreas Mogensen radioed the crew from mission control in Houston.
- Floating in the Quest airlock, astronauts Mike Hopkins and Victor Glover switched their suits to battery power at 6:28 a.m. EST to officially kick off 233rd spacewalk in station history and the first so far this year. It was the third spacewalk for Hopkins and the first for Glover.
- After floating out of the airlock, Glover attached a foot restraint to the end of the space station's robot arm and rode the space crane to the European Space Agency's Columbus module where he and Hopkins installed a high-speed Ka-band data relay antenna.
- Flight controllers initially had problems activating a heater in the antenna, but after Hopkins unplugged and re-connected a power cable, the system began working normally.
- The spacewalkers then worked to route cables and to connect the Bartolomeo experiment platform to the Columbus module, providing power and data relay to experiment and instrument attachment points.
- Bartolomeo was delivered to the station last spring aboard a SpaceX cargo ship and attached to Columbus using the robot arm. The platform will be used to mount a variety of external experiment packages that can be changed out as needed for research.
- "We have been preparing for the better part of a year as we awaited the arrival of the Bartolomeo platform," said flight director Rick Henfling. "It arrived on the SpaceX CRS-20 (cargo) mission last April. It was installed robotically, and now we have a few more tasks, using our spacewalkers to hook up the power and data connections."
- But Hopkins and Glover were only able to get four of six cables properly connected. While Hopkins worked to resolve the problem, Glover, still riding on the end of the robot arm, carried a protective cover that had been attached to the new antenna to a point well away from the main body of the station.
- Once in position, seeming to float alone in orbital darkness, Glover pushed the boxy antenna cover away on a trajectory that ensured it would not make its way back to the station's vicinity before re-entering the atmosphere and burning up.
- Unable to resolve the cable trouble, Hopkins capped the two balky connectors and used tie-downs to hold all the cables in place.
- Both spacewalkers then made their way to the far left end of the station's power truss and removed two solar array ground handling fixtures. The so-called "H fixtures" are being taken off to make way for new solar panels that will be attached to the existing arrays later to boost the lab's power output.
- Today's spacewalk came to an end at 1:24 p.m. after six hours and 56 minutes.
- Hopkins and Glover plan to carry out a second spacewalk next week to remove additional H fixtures, to complete work to install a replacement solar array battery and to replace cameras on the power truss, the Destiny lab module and on a Japanese robot arm.
• January 27, 2021: NASA astronauts Mike Hopkins and Victor Glover concluded their spacewalk at 1:24 p.m. EST, after 6 hours and 56 minutes. The two NASA astronauts completed a number of tasks designed to upgrade International Space Station systems. 14)
- The crew installed a Ka-band antenna, known as ColKa, on the outside of the ESA (European Space Agency) Columbus module, which will enable an independent, high-bandwidth communication link to European ground stations. Bartolomeo is partially operational and in a safe configuration following the connection of four of six cables to the science platform, and the final two cables that could not be connected will be attended to on a future spacewalk.
Figure 9: Spacewalkers Victor Glover (top) and Michael Hopkins are pictured working on upgrades to the Bartolomeo science platform attached to Europe's Columbus lab module (image credit: NASA TV)
- During the spacewalk, Hopkins and Glover also removed a pair of grapple fixture brackets on the far port (left) truss in preparation for future power system upgrades. Glover also worked to replace a suspected broken pin inside the station's airlock as a "get ahead" task, but teams determined that a replacement pin was not needed after an inspection confirmed the current pin to be functioning properly.
- Space station crew members have conducted 233 spacewalks in support of assembly and maintenance of the orbiting laboratory. Spacewalkers have now spent a total of 61 days, 1 hours, and 47 minutes working outside the station.
- Hopkins has now completed his third spacewalk for total of 19 hours and 54 minutes outside the space station. This was the first spacewalk for Glover with a total of 6 hours and 56 minutes.
- On Feb. 1, Hopkins and Glover will conduct another spacewalk to address a variety of tasks, including installation of a final lithium-ion battery adapter plate on the port 4 (P4) truss that will wrap up battery replacement work begun in January 2017. Hopkins and Glover will remove another grapple fixture bracket on the same truss segment, replace an external camera on the starboard truss, install a new high-definition camera on the Destiny laboratory, and replace components for the Japanese robotic arm's camera system outside the Kibo module.
• January 26, 2021: Lights, camera, action for NASA astronauts Michael Hopkins and Victor Glover. The duo will install European payloads outside the International Space Station during a spacewalk on 27 January, guided by the know-how of their colleagues. 15)
Figure 10: ESA astronaut Andreas Mogensen is seen in this image installing the Columbus Ka-band or ColKa terminal that will enable faster communication with Europe during a ‘dress rehearsal' in the Neutral Buoyancy Lab at NASA's Johnson Space Center in Houston, Texas in 2018 (image credit: NASA EVA NBL)
- Andrea will serve as ground IV, directing Mike and Victor through the installation of the small fridge-sized device by radio from NASA's mission control.
- ColKa will connect the Columbus module to the European Data Relay System, satellites in geostationary orbit that transfer data via European ground stations. This will enable faster uplink and downlink speeds between the European segment of the Space Station and European researchers on the ground.
- In addition to installing ColKa, the pair will also complete cable and antenna rigging for the Bartolomeo science platform outside Columbus.
- The Bartolomeo service will provide end-to-end access for external payloads on the Space Station. A new community of start-ups and space entrepreneurs will benefit from an unobstructed view of Earth, direct control of experiments from the ground and the possibility of retrieving samples.
• January 19, 2021: Astronauts aboard the International Space Station are planning a spacewalk to install a high-speed satellite link that will improve their connections with Europe. 16)
The system will enable astronauts to connect at home broadband internet speeds – delivering a whole family's worth of video streaming for communications and a data pipeline connecting the scientific experiments aboard the Station to researchers in Europe.
The 20-year-old Station – which was built when the internet was in its infancy – will be equipped with a dedicated European autonomous communications module, complementing the connectivity provided by a US satellite communications system.
The small fridge-sized device to be installed on the outside of the ESA Columbus module of the Station will send signals into space, where they will be picked up by a European telecommunications satellite in geostationary orbit 36,000 km above Earth – some 90 times the height of the Station.
The satellite is part of the EDRS (European Data Relay System) and will enable internet-like connectivity with the Station, relaying data directly between the Station and European soil via the system's ground station in Harwell in the UK.
NASA astronauts Michael Hopkins and Victor Glover are due to install the communications device during a spacewalk on 27 January. The device – nicknamed ColKa (Columbus Ka-band terminal), connects to a plug outside the Columbus module that will relay the data to and from the astronauts computers inside.
The state-of-the-art system will ensure faster communications by using European infrastructure to relay data to the ground for experiments in the Columbus module, allowing researchers on Earth to access their experiments in real time when the Station is within range of EDRS. ColKa will provide speeds of up to 50 Mbit/s for downlink and up to 2 Mbit/s for uplink.
It was designed and built by British and Italian companies, using products from Belgium, Canada, France, Germany and Norway, some of which have been qualified under the ESA's ARTES (Advanced Research in Telecommunications Systems) program.
ColKa will use the EDRS infrastructure developed as a telecommunications Partnership Project between ESA and Airbus, as part of ESA's efforts to federate industry around large-scale programs, stimulating technology developments to achieve economic benefits.
The know-how gained from designing, building and running ColKa will be instrumental for ESA's communications package under the ESPRIT communications and refuelling module that is being designed for the lunar Gateway – an outpost over 1000 times farther from Earth than the International Space Station that will provide vital support for a sustainable, long-term human return to the lunar surface.
Figure 11: In the past, astronauts trained at NASA's Neutral Buoyancy Laboratory in Houston to install the ColKa high-speed satellite link device to the International Space Station that will improve their connections with Europe (image credit: NASA)
The Jan. 27 spacewalk will focus on completing cable and antenna rigging for the "Bartolomeo" science payloads platform outside the ESA (European Space Agency) Columbus module. The duo also will configure a Ka-band terminal that will enable an independent, high-bandwidth communication link to European ground stations. After completing the upgrades on the Columbus module, Hopkins and Glover will remove a grapple fixture bracket on the far port (left) truss in preparation for future power system upgrades. 17)
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The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: "Observation of the Earth and Its Environment: Survey of Missions and Sensors" (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (firstname.lastname@example.org).