Reconfigure FIR coefficients without stopping the sampling process

Hello Everyone,

I have a quick question regarding the reconfiguration of blocks within a
gnuradio “top block” application. I am working on a radar system that
occasionally attempt to switch transmission waveforms due to results of
processed data. Consequently, the back end processing will have to
simultaneously, namely the FIR filter coefficients. Currently, I have a
“top block” application working properly when the radar is operating for
fixed waveform. This application is initiated as a parallel process
from a
parent program, and continuously takes data until the parent program is

Here is small portion of the code that is of interest:

gr_matchfil = [gr.fir_filter_ccf(1, fr ) , gr.fir_filter_ccf(1, fr )]

for i in range(numchan):
fg.connect((u,i), (gr_decimation[i],0))
fg.connect((gr_decimation[i],0), (gr_matchfil[i],0))
fg.connect((gr_matchfil[i],0), (gr_interleave,i))

fg.connect((gr_interleave,0), (fsink,0))

What I would like to do is alter the the coefficients “fr” in the
“gr_matchfil” from the parent program without stopping the sampling
I figure that this will have to do something with accessing the shared
memory of the parallel process. Would this be possibly after
is executed. If anybody has any ideas on how to achieve this, it would
greatly appreciated.


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