The initial element of the Amateur Radio on the International Space Station (ARISS) next-generation radio system has been installed onboard the ISS, and amateur radio operations using the new gear are now under way. The first element, dubbed the InterOperable Radio System (IORS), was installed in the ISS Columbus module. The IORS replaces the Ericsson radio system and packet module that were originally certified for spaceflight in mid-2000.

“Finally! It's been a scramble the last few days with coordination over the weekend and yesterday with astronaut Chris Cassidy, KF5KDR,” ARISS-US Delegate for ARRL Rosalie White, K1STO, said. “But the new ARISS radio system is now installed, set up, and functioning. What a long road we’ve traveled over the past 5 years!”

Initial operation of the new radio system is in FM cross-band repeater mode using an uplink of 145.99 MHz (CTCSS 67 Hz) and a downlink of 437.800 MHz. System activation was first observed at 01:02 UTC on September 2. Special operations will continue to be announced, ARISS said.

The IORS was launched from Kennedy Space Center last March onboard the SpaceX CRS-20 resupply mission. It consists of a special, “space-modified” JVC-Kenwood D710GA transceiver, an ARISS-developed multi-voltage power supply, and interconnecting cables. The design, development, fabrication, testing, and launch of the first IORS was the culmination of a 5-year engineering effort by the ARISS hardware team of volunteers.

ARISS says the system “will enable new, exciting capabilities for ham radio operators, students, and the general public.” Capabilities include a higher-power radio, voice repeater, digital packet radio (APRS) capabilities, and a Kenwood VC-H1 slow-scan television (SSTV) system.

A second IORS will undergo flight certification for later launch and installation in the Russian Service Module. The second system enables dual, simultaneous operations, such as voice repeater and APRS packet. It also provides on-orbit redundancy to ensure continuous operations in the event of an IORS component failure.

“Next-gen development efforts continue,” ARISS said. “For the IORS, parts are being procured and a total of 10 systems are being fabricated to support flight, additional flight spares, ground testing, and astronaut training.” Follow-on next-generation radio system elements include L-band repeater uplink capability — currently in development — and a flight Raspberry-Pi, dubbed “ARISS-Pi,” that is just in the design phase. The ARISS-Pi promises operations autonomy and enhanced SSTV operations, ARISS explained.

ARISS this year marks 20 years of continuous amateur radio operations on the ISS. The largely volunteer organization welcomes donations to the ARISS program for next-generation hardware development, operation, education, and administration.