ARISS Looks Forward to Installation of “Ham Video” on Space Station
The Amateur Radio on the International Space Station (ARISS) program is hoping its “Ham Video” digital television transmitter, now stowed onboard the International Space Station (ISS), will be installed and commissioned this fall. US Astronaut Mike Hopkins, KF5LJG, who heads into space September 25, is scheduled to handle the tasks involved with getting the S Band Ham Video DATV setup on the air from the ISS Columbus Laboratory. The project has a low priority, however, and it could be a while before live digital TV images show up from the ISS. According to ARISS-EU Chairman Gaston Bertels, ON4WF, live commissioning will take place in stages, each during a full pass of the ISS over the Italian Space Agency’s Very Long Baseline Interferometry station near Matera in southern Italy. That station will be used to receive the DATV signal from the ISS.
“It is not yet known if these passes will be chosen in close succession, or if they will cover several weeks,” Bertels said in a recent Ham Video update. ARISS has proposed that the European Space Agency (ESA) transmit over all continents, with the camera turned off between commissioning passes. The camera operates from batteries, and having to service it could require a prohibitive amount of crew time, always at a premium.
“During commissioning activities, the astronaut will activate the Ham Video transmitter with the camera live in all possible configurations — two antennas, four frequencies and two symbol rates,” Bertels told ARRL. “This will be done during three or four passes of the ISS over southern Italy, where the operating ground station is located.”
Bertels said the transmitter typically would be activated only during passes over the ground station and shut down after each activity. “What we are asking ESA to do is to leave the transmitter on, without camera, between commissioning passes,” he said. “Once commissioning is complete, the Ham Video transmitter will be shut down, and how it’s used after that is still under discussion.
A blank signal contains everything ground stations need to set up and fine tune reception, Bertels said. Data collected will be used to study the performance the ARISS L/S band antennas, now installed on Columbus, as well as to evaluate the global system.
Ham Video Wants You!
ARISS is calling on members of the Amateur Radio community, especially those interested in space communication, to collaborate on the project, and Bertels said several satellite operators already have shown interest. Ham Video technical characteristics are available on the ARISS-EU website at the “Ham Video” link in the left sidebar.
Among the components of a satellite ground station, the antenna system is the most expensive. High-gain antennas equipped with azimuth/elevation capability and driven by an appropriate computer program are necessary. “For Ham Video reception, a 1.2 meter dish with precision tracking is recommended,” Bertels said. Properly equipped stations should be able to receive from 3 to 4 minutes of video on a given ISS pass. But even stations with simpler equipment may be able to gather useful data. Chained stations will be needed for ARISS Ham Video school contacts, although that prospect is still in the future at this point.
ARISS-EU says a “simple station” might consist of a helix-fed parabola dish; a low-noise downconverter (such as a High Sierra Microwave Model 2400, Kuhne Electronic KU LNC 23 TM, or Ali Express HD LNBF); a DVB-S receiver on a computer card (such as the Techno Trend S2-1600), and the free Tutioune software developed by Jean Pierre Courjaud, F6DZP.
With this setup, Ham Video from the ISS can be received, decoded and viewed on a computer display. The Tutioune software graphically displays received signal characteristics and can save data to a file for forwarding to ARISS for analysis.
Dry Run Tests Successful
An Ham Video experiment sequence test (EST) was carried out in late August, and simulation tests were completed early this month. The EST consisted of a series of ground station tests using IK1SLD in northern Italy. A very low power transmitter installed in the shack, transmitted a DATV recording on the Ham Video frequencies. IK1SLD received and decoded the signal and streamed it on the web.
ESA’s Belgian User Support and Operations Center (BUSOC) and the European Astronaut Center (EAC) in Germany also conducted tests from Kayser Italia’s laboratory, where an engineering model Ham Video unit is operational. Kayser Italia manufactured the Ham Video unit. IK1SLD and IØKPT produced, received and streamed signals to the web using various configurations.
For the simulations BUSOC supervised from Brussels and ARISS participants IØKPT and F6DZP operated from home. The simulations were done in the Columbus mockup at the EAC, where a nonoperational Ham Video model was installed for astronaut training. Ham Video transmissions were simulated at different frequencies and symbol rates, and video was streamed to the web from the Columbus mockup.
Four “passes” were simulated, using both ARISS antennas. One major goal of the simulations was to check the efficiency of communications between ground and “crew.” The simulations were considered a success, and lessons were learned for gaining time in transmitting commands. This is important, considering the 8 minute limit on contact time during real commissioning. — ARISS-Europe Chair Gaston Bertels, ON4WF