GNU Radio is an open source digital signal processing (DSP) toolkit which is often used to implement decoders, demodulators and various other SDR algorithms. Several SDR programs are based on GNU Radio code, and it is responsible for a lot of DSP development and knowledge within the SDR and radio community. It is compatible with almost all SDR devices, including the RTL-SDR.
Recently GNU Radio has been updated to version 18.104.22.168. The release is classed as the first "minor" release version in six years, as they are going from version 3.7 to 3.8. That doesn't mean there have been no changes for six years, it just means that over the last six years all releases have remained within the 3.7 version and they have mostly been bug fixes rather than larger changes like added features. Behind the scenes over the last six years developers have been working on these larger changes, and now is the time that they have been officially released.
Marcus Müller from GNU Radio writes:
Tonight, we release GNU Radio 22.214.171.124.
It’s the first minor release version since more than six years, not without pride this community stands to face the brightest future SDR on general purpose hardware ever had.
Since we’ve not been documenting changes in the shape of a Changelog for the whole of the development that happened since GNU Radio 3.7.0, I’m afraid that these release notes will be more of a GLTL;DR (git log too long; didn’t read) than a detailed account of what has changed.
What has not changed is the fact that GNU Radio is centered around a very simple truth:
Let the developers hack on DSP. Software interfaces are for humans, not the other way around.
And so, compared to the later 3.7 releases, nothing has fundamentally modified the way one develops signal processing systems with GNU Radio: You write blocks, and you combine blocks to be part of a larger signal processing flow graph.
With that as a success story, we of course have faced quite a bit of change in the systems we use to develop and in the people that develop GNU Radio. This has lead to several changes that weren’t compatible with 3.7.
The changelog is too long to quote here, but as a summary they have fixed bugs, updated dependencies to newer versions, enabled C++ code generation, changed XML to YAML, moved from QT4 to QT5 and removed a few stale projects. Some of these changes could break compatibility with older GNU Radio tutorials and programs. It also seems that unfortunately due to a lack of updates, support for the Funcube Dongle has been removed.