Alpha =0.001 in gr.probe_avg_mag_sqrd_cf

GNU Radio
1

Hi all

I had a problem with tunnel.py, but changing threshold from 30dB to 50dB
it was solved, now I’m reading receive_path.py in carrier sensing blocks
are defined alpha=0.001 and thres=30 for use with
gr.probe_avg_mag_sqrd_cf, please can somebody tell me what is alpha
value and why is set to 0.001?

Thanks for your help

Juan Q.

2

On 06/03/2010 11:54 PM, Juan Q. wrote:

Hi all

I had a problem with tunnel.py, but changing threshold from 30dB to 50dB it was solved, now I’m reading receive_path.py in carrier sensing blocks are defined alpha=0.001 and thres=30 for use with gr.probe_avg_mag_sqrd_cf, please can somebody tell me what is alpha value and why is set to 0.001?

Alpha is the pole placement in the single pole IIR filter, used to
filter the signal before it is compared with the threshold. Details may
be found in
gnuradio/gnuradio-core/src/lib/filter/gr_single_pole_iir_filter_xx.cc

Mattias