“Ham Video” Transmits Live Images of Astronaut Mike Hopkins, KF5LJG, From the ISS
As one of his final actions during his duty tour aboard the International Space Station, NASA Astronaut Mike Hopkins, KF5LJG, installed and commissioned the Amateur Radio on the International Space Station (ARISS) “Ham Video” system over the March 8-9 weekend. Hopkins returned safely to Earth March 10 aboard a Soyuz lander with crew members, Russian cosmonauts Oleg Kotov and Sergey Ryazansky. The Amateur Radio digital television (DATV) setup can transmit video of the crew and the interior of the Columbus module on the 2.4 GHz band (S-band). The ARISS project, led by ARISS-EU, AMSAT-Italy, and the European Space Agency (ESA), eventually will enhance ARISS school contacts by providing a video and audio downlink plus an audio-only uplink. Operating under the call sign OR4ISS, the S-band transmitter can be connected to one of two ARISS patch antennas already installed on Columbus. Radiated RF power is on the order of 10 W EIRP. The received DATV signal was streamed via the web to a global audience via the British Amateur Television Club (BATC) server.
“Congratulations to the Ham TV team on today’s outstanding commissioning success!” said ARISS International Chair Frank Bauer, KA3HDO, who works for NASA. “Several stations in Italy were able to receive [the] video and audio downlink.” He explained that while the video camera and transmitter aboard the ISS are referred to as “Ham Video,” the entire digital TV/audio downlink and FM voice uplink system is being called “Ham TV.”
The commissioning process primarily involved making sure that ground stations in Europe would be able to copy the DTV downlink signal, and the results exceeded expectations. A large, high-gain dish at the Matera, Italy, ground station worked in concert with smaller-dish stations that are planned as future Ham TV ground relay stations. ARISS had several additional ground stations around the world tuned in and providing reception reports of the so-called “blank transmission” mode, with the transmitter on and the camera turned off. Those blank transmissions will continue until the next commissioning step set for April 12, and ARISS invites reports.
Years of Planning
Commissioning of the Ham TV system marked the culmination of more than a decade of planning and preparation within ARISS. Funding was an issue until Italian astronaut Paolo Nespoli, IZ0PA, who had handled numerous ARISS school contacts during ISS tenure in 2010 and 2011, championed the project. A plan for an Amateur Radio DATV transmitter was presented to ESA’s educational services. The proposal was accepted in 2012, and a contract signed with Kayser Italia to develop and manufacture the DATV S-band transmitter. Commissioning initially had been scheduled to take place last year but was postponed several times.
“As many of you know, it is quite a challenge to develop, certify, fly and operate equipment on the ISS,” Bauer pointed out in a post to the ARISS-Press list. He said the Ham TV system faced additional challenges that included a wide-bandwidth signal that requires very weak signal reception and is subject to extreme Doppler effect. In addition, he noted, S-Band spectrum is shared with “the ubiquitous WiFi signals.” The ARISS team developed several innovative design techniques and mitigation strategies to work around each challenge, he said, and was ready to start Ham TV experimentation.
As ARISS-Italia posted on its Facebook page, “The ARISS Ham TV project will make possible to view the astronauts and their ISS living habitat to ground stations operated by radio amateurs.” Although there are no immediate plans to employ the Ham TV system for educational contacts with schools in North America, Bauer said several US radio amateurs are testing this capability, as are stations in other parts of the world. “If this shows educational value,” Bauer said, “it will be employed in the US.” — Thanks to AMSAT News Service, ARISS-EU Chairman Gaston Bertels, ON4WF, ARISS International, and Frank Bauer, KA3HDO
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