> As some of you know, I've been involved with GNU Radio for a long > time. The idea that became GNU Radio started as a conversation over > dinner in San Francisco with John Gilmore, something like 10 years > ago.
As one of the guys present at that dinner in early 2001, let me suggest that Eric has done an incredible job picking up that idea and running with it for a decade. We saw that commercial companies were using digital signal processing to radically simplify and improve their products, but that the free software world hadn't learned those lessons. That meant there was a real opportunity hanging wide-open. Eric jumped on it. Part of the deal was that I'd pay his salary for the first year or two, because I knew you can't really get much public support or financial support for a free software project until it can actually do some useful job. Eric spent the first year learning modern signal processing, surveying existing hardware and existing free software, then settled on MIT's "spectra/pspectra" code base as a good place to start hacking. After the first few years, he found enough academic and commercial support for GNU Radio that I didn't need to pay him full time -- and he weaned himself fully off my support shortly afterward. Matt Ettus was an early volunteer who also saw the real-world promise in free signal processing software. We had reasonable software, but the available high speed A/D and D/A hardware cost thousands of dollars and was pretty lame. Matt finished his job designing Bluetooth circuitry, and then risked everything to design and build what became the USRP. With Eric's help, he built up from nothing to a one-man design/procurement/manufacturing/stocking/shipping/sales/customer-support/programming shop, which over the years has matured into the thriving and valuable business it is today. Jay Lepreau was another early contributor who saw how GNU Radio could enable active academic research into cognitive radios. Jay brought us into his lab at the University of Utah, encouraging researchers at dozens of other institutions to design their experiments on GNU Radio and the USRP. He brought us into the academic funding that significantly matured GNU Radio's ability to do packet-based communication. Jay died in 2008 but his contributions live on in this community. Along the way we took a few detours into application areas that tested and honed GNU Radio's strengths. While Hollywood was trying to force the FCC to outlaw TV receivers that could receive free over-the-air digital TV signals (because they'd forgotten to put DRM into them), Eric and a small team successfully implemented an HDTV receiver using old PCI-bus digitizer boards and GNU Radio. Hollywood's engineers said it couldn't be done, and we knew they were liars, so we did it. Indeed, it ran 30x slower than realtime on a dual Athlon motherboard. But it ran, decoded actual TV signals, and proved to the regulators and to the standards committee that you'd have to not only outlaw hardware demodulators, but also software -- which EFF had recently proven to a Federal appeals court was a violation of the First Amendment. The fucking bastards at the FCC passed the regulation anyway (https://secure.wikimedia.org/wikipedia/en/wiki/Broadcast_Flag), but the American Library Association and Public Knowledge litigated in federal court, proved that the FCC had no authority to regulate what receivers do with their signals after reception, and the rule was struck down. This HDTV demodulator code is *still* not running in the latest version of GNU Radio, but I hope someone will work out the kinks. Modern hardware should be able to do it in realtime. A second big attempted application area was passive radar. We read that the US Army's favorite tactic when invading somewhere was to blow up all the TV and radio stations because it's easy to track airplanes by watching their signals bounce off the planes. It works with cellphone tower signals, too. Eric spent several years researching the topic, writing GNU Radio code, and designing antennas and hardware. Ultimately none of it worked reliably; it took more dynamic range (or custom differential hardware) than we had, but we learned a lot and have made it easier for future generations to do this as the hardware improves. Eric, it's been a great decade, and I'm looking forward to the next big trouble you get into! John _______________________________________________ Discuss-gnuradio mailing list Discussemail@example.com http://lists.gnu.org/mailman/listinfo/discuss-gnuradio