Re: Are there firls and kaiser filter methods for C++ OOT?

[Marcin Puchlik]

Hi George,

I also tried to use low_pass() function in my C++ program but with no luck. My linker shouts that there is undefined reference to this function but headers where recognized.

How did you install the GNU Radio? Was it installation from PPA or building from source?

Marcin

pon., 21 lut 2022 o 18:28 George Edwards <gedwards.eng@gmail.com> napisał(a):

Hi Marcin,

Thanks again for your help! I was a little busy and finally got around to looking at the two C++ fir filter documents you sent me.

I tried to design an OOT C++ FIR lowpass filter block based on my understanding of these documents but my code shows error (squidly). In the OOT C++ code, I included all the #include header files shown in the documents. Then using the first document above for the lowpass design, I wrote the following:

vector <float> lpfilter; 

then, I defined all the filter parameters (give them value) and tried to use the filter method:

lpfilter = gr::filter::firdes::low_pass(gain, sampling_freq, cutoff_freq, transition_bandwidth,

fft::window::win_type window = fft::window::win_type::WIN_HAMMING, beta = 6.76);

This failed and showed a squidly across the line with fft::window::win_type....! I also tried leaving off the gr::filter::firdes     

nothing worked and I included the fft window header file!

Please send me code examples if you have any that shows how to use these functions/methods.

One more question: on a search on the second document, it says the remez filter_types are: one of "bandpass", "hilbert" or "differentiator", I would have thought lowpass filters would be included??

Thank you!

George

On Mon, Feb 14, 2022 at 12:05 AM Marcin Puchlik <m.puchlik@is-wireless.com> wrote:

Hello George,

Yes, there is. Check this out:

https://www.gnuradio.org/doc/doxygen/firdes_8h_source.html

https://www.gnuradio.org/doc/doxygen/pm__remez_8h.html

BR, 

Marcin

pon., 14 lut 2022 o 00:07 George Edwards <gedwards.eng@gmail.com> napisał(a):

Hello GNURadio Community,

I am designing a Gnuradio OOT block in C++. Are there firls and kaiser filter methods (analogous to the scipy package methods that one would use in Python OOT) that I can call to generate coefficients.

Thank you!

Regards,

George