ARRL Life Member Ulrich Rohde, N1UL, has donated a Rohde & Schwarz SMBV100A vector signal generator to the ARRL Laboratory. The device offers internal signal generation for all major digital radio standards. “That is absolutely fabulous news and extremely generous,” ARRL CEO David Minster, NA2AA, told Rohde.
ARRL Laboratory Manager Ed Hare, W1RF, said the instrument will be a valuable addition to the Lab’s testing capabilities.
“We will be able to do more comprehensive tests on modern radios, almost all of which use software-define radio technology,” Hare said. “We will also be able to add testing of receiver’s digital capability. The flexibility of this generator will serve the Laboratory for years to come.”
Hare said he was looking forward to learning more about the SMBV100A once it’s installed at the Lab. “The potential is really exciting,” he said. “As always, we appreciate the support that Ulrich Rohde has given to the Lab over the past several decades.”
Rohde said vector signal generators are the logical successors to the older AM/FM modulation-capable signal generators and have practically unlimited use capability. “For some of the tests required to characterize a software defined radio (SDR), we need different test equipment,” he said. Rohde noted that the SMBV100A has a built-in arbitrary waveform generator capable of operating up to 6 GHz, with “many complex signals in it library, and also has the familiar AM/FM simple mode”
Going from analog to digital SDRs, large-signal behavior is best determined with special multi-carrier signals, Rohde said. Instead of a two-tone test signal for, say, measuring IF characteristics, the SMBV100A can generate up to 30 discrete tones. Rohde said the SMBV100A can produce any signal “as long as you can describe it mathematically,” even an FT8 signal. The bottom line is a more realistic test result.
Rohde said that in 1982, while he headed the Department of Defense Radio Division at RCA, he and his engineering group “invented what is now called the software defined radio,” which was considered classified military information at the time.