As some of you know, beginning of this month I presented a new
GNURadio block I wrote that implements a RTSA like spectrum
visualization of the spectrum similar to those found on R&S / Agilent
/ Tek equipement.
I’ve just pushed the latest version of it on git and this includes a
proper integration with either the WX or QT GUI of gnuradio. And I
thought this would be a good occasion to also make the announce on
this mailing list for those who didn’t attend GRC and are not
following the IRC channel.
The home page of the project can be found at
There isn’t much information there, but you’ll find a few screen shot
of what the display looks like which will hopefully convince you to
try it out for yourself. Believe me it’s even better when it moves
As the title says, the block relies on GPU acceleration. The
computations are pretty heavy since every single input sample will be
processed (as opposed to the current FFT sinks that just do periodic
snaptshots), thereforce GPU acceleration is pretty much a must to
support the very wideband devices like hackrf/bladerf/b200 …
More precisely it uses OpenCL and OpenGL and the data sharing
extension between the two (known as CL/GL interop). That means that to
use it, you’ll need hardware that supports those and the appropriate
drivers. For OSX that shouldn’t be much of an issue if the machine has
a decent GPU. For Linux, you’ll need the binary drivers for either AMD
or NVidia. Intel cards on linux most likely won’t work. Although the
more recent hardware can handle it, Intel decided to limit OpenCL
support to Windows (and possibly OSX, not sure).
It would be very helpful if you could report success / failure so we
can try to list what hardware is out there and which works / which
For the installation you can grab the sources from git :
It’s only compatible with Gnuradio 3.7 and I’m not planning to
backport it, it’s about time people update.
You will also needs a few dependencies such as freetype2 and glfw3.
For the latter, make sure to use version 3.x and to build it wit
A MacPort port and a PyBOMB recipe are also in the works and should
soon be available.
Also, you should make sure to use a very recent version of Gnuradio
since some of the required fixes were just merged today. To take
advantage of gr-fosphor from inside osmocom_fft, you’ll also want to
update your gr-osmosdr source block and use the -F option when
starting osmocom_fft to enable the WX fosphor widget.
Finally, I’d like to say a big thanks to my fellow osmocom members and
the people on IRC who did a lot of testing on various hardware and
platforms to try to make this release work “out of the box” for as
many people as possible.