Re: How to compute FFT and IFFT in C++ OOT?

FFT support is built in to GNU Radio with FFTW. Here's how it's done. First, define it in your foo_impl.h file. The options are fft_complex_fwd, fft_complex_rev, fft_real_fwd and fft_real_rev. https://github.com/drmpeg/gr-paint/blob/master/lib/paint_bc_impl.h#L25

How to compute FFT and IFFT in C++ OOT?

Dear GNURadio Community: I am writing a C++ OOT block where the signal processing requires the computation of both fft and ifft. Is there any Gnuradio C++ functions for the fft and ifft? If not, is there any way to wrap in Python's libraries with these methods into C++ OOT? Thank you! Regards,

RE: Reed-Solomon Decoding (Not for Digital Television)

Hello Ron and Daniel, First of all I appreciate the replies, you've given me some great starting places for this, so thanks. I guess my next question would be how to implement this into my existing flowgraph given the output of my demodulator and the input of the blocks. Right now I have my G

Re: Does complex conjugate invert IQ ?

Indeed. Also, in case that's a long read (I think it's interesting anyhow), the bottom line is that IQ swap and complex conjugate are basically "the same" operation for most purposes. This is because if the swap is S(a+bi) = b+ai and the conjugate is C(a+bi) = a-bi, then S(z) = iC(z), so we se

Re: Reed-Solomon Decoding (Not for Digital Television)

Hi Patrick and Ron, Besides the DVB-T Reed-Solomon blocks, there is also the Reed-Solomon blocks from gr-satellites. The gr-satellites blocks expose a couple more parameters about the Reed-Solomon code definition. These are the "first consecutive root" and the "primitive element". These parame

Re: Does complex conjugate invert IQ ?

On 2021-12-13 11:14, Albin Stigö wrote: This might be of interest. https://www.dsprelated.com/showarticle/51.php The attached shows that a complex-conjugate will nicely effect a frequency inversion, if that's what is wanted. inversion.grc Description: application/gnuradio-grc

Re: OOT Binding problem

Si how to use the command "gr_modtool bind" ? Marcus Müller a écrit >You can't, GNU Radio links against that. >I'd recommend not updating Python, you essentially can't. > >On 14.12.21 14:44, Fabien PELLET wrote: >> castxml was installed, pygccxml also in v1.9.1. I upgrade pygccxml to 2

Re: OOT Binding problem

You can't, GNU Radio links against that. I'd recommend not updating Python, you essentially can't. On 14.12.21 14:44, Fabien PELLET wrote: castxml was installed, pygccxml also in v1.9.1. I upgrade pygccxml to 2.2.1 without success. How to update python version (3.7 actually) without having to

Re: Peaks when increasing the FFT lenght ofdm example

Hi Pedro, we'd need more info to tell why you observe these peaks. How large are your input packets? Do they span multiple OFDM symbols? How many subcarriers are active? Your peaks hint at some kind of repetition or lot's of zeros. Cheers Johannes On 14.12.21 13:07, Pedro Viegas wrote: Hi

Re: OOT Binding problem

castxml was installed, pygccxml also in v1.9.1. I upgrade pygccxml to 2.2.1 without success. How to update python version (3.7 actually) without having to recompile gnuradio ? Le 14/12/2021 à 12:44, Josh Morman a écrit : Sounds like castxml could be playing a role here.  Along the same lines

Peaks when increasing the FFT lenght ofdm example

Hi everyone, I'm having a problem when I increase the number of carriers from 64 to 512 in the gnuradio OFDM example. When the number of carriers is 512, the complex envelope of the signal in the time domain has some peaks, which I can not have for the test I'm trying to make. Can anyone tell why

Re: OOT Binding problem

Sounds like castxml could be playing a role here. Along the same lines Ron suggested, you could try installing both pygccxml and castxml from pip3 Josh On Tue, Dec 14, 2021 at 6:23 AM Ron Economos wrote: > I've tried it on both Ubuntu 18.04 and 20.04, so I don't think it's due > to the Python

Re: OOT Binding problem

I've tried it on both Ubuntu 18.04 and 20.04, so I don't think it's due to the Python version. You could try the latest pygccxml. Use pip or pip3 to install. You could also try building CastXML from source. That's where some of the compiler dirty work is being done. For example, you need the l

Re: OOT Binding problem

Is that could be an incompatibility between Python3.7 that is provide by RaspiOS repo and Pybind11 ? Fabien. Le 14/12/2021 à 11:54, Marcus Müller a écrit : Uh, since bindtool is Python-only, this should really not be platform-dependent. Unless we've got a problem with pygccxml, that is... On

Re: OOT Binding problem

Uh, since bindtool is Python-only, this should really not be platform-dependent. Unless we've got a problem with pygccxml, that is... On 14/12/2021 11.51, Ron Economos wrote: I've never been able to get gr_modtool bind to work on 32-bit ARM architecture (Ubuntu on a Beagleboard-X15). I get the

Re: OOT Binding problem

I've never been able to get gr_modtool bind to work on 32-bit ARM architecture (Ubuntu on a Beagleboard-X15). I get the same error message. Ron On 12/14/21 2:15 AM, Fabien PELLET wrote: Hello, I'm trying to write a simple OOT module. For exemple, I create a module "test" (gr-modtool newmod t

OOT Binding problem

Hello, I'm trying to write a simple OOT module. For exemple, I create a module "test" (gr-modtool newmod test) and I create a general block inside (gr-modtool add blablamodule) : everything fine up to this point. If now I modify the file "blablamodule.h" I have do a "gr_modtool bind blablamo