gr-notchFIlter

An OOT(out-of-tree) module for gnuradio, tyring to implement notch filter

#Requirements

based on gnuradio 3.9+

Installation

As recommanded by gnuradio installation guide, the OOT should better be installed from source.

First, download the package and unzip to a local folder.

Enter the folder consisting 'build' folder.

Open terminal here.

Enter the 'build' folder:

cd build

run cmake and make:

cmake ..

make

sudo make install

link the module to the system:

sudo ldconfig

Blocks

adaptiveNotch

An adaptive notch filter with LMS method. Two parameters are needed: sampRate, targetFreq.

This block first generate a cosin function (f1) and a sin function (f2), and combine them by:

y=w1*f1+w2*f2

than compare y with input signal:

e=input-y

e also functions as output signal

than update w1 and w2:

w1=0.01e*f1

w2=0.01e*f2

iirnotch

An iir notch filter. transfer function is

(s*s+wc*wc)(s*s+wc*wc+wb*s)

wc is the target frequency to be filtered

wb is the bandwidth to be filtered