Convert White noise added ECG signal into binary

Hi,

I am trying to convert an ECG signal into binary format. I have added noise to the ECG signal using awgn function. Now i need to convert this signal to binary format to give as an input to a filter. the commands i have given are,

load('ECG signal name')

plot(val(9,:))

z = awgn(val,0.5);

now z needs to be converted into binary format.

Please help how to do this.

[Mehmed Saad]

what is the threshold to convert it to binary?

for example, if greater than threshold 1 otherwise 0

[Kumari Surbhi]

I am not sure threshold value needs to defined. It is simply conversion from fractional decimal to binary conversion. e.g. using de2bi function. But this function only applies to integers.

Answer 1

[Mehmed Saad]

Load ECG Signal

load('mit200.mat')

Make it all positive

shift_up = min(ecgsig);
ecg_n = ecgsig-shift_up;

Normalize it (0 to 1)

norm_1 = max(ecg_n);
ecg_n = ecg_n/norm_1;

convert it to I32

ecg_i32 = uint32(round(ecg_n*2^32));

Now your signal is converted in u32, you can use de2bi

ecg_b = de2bi(ecg_u32,32);

The signal ecg_b is the binary for of your ecg signal

To convert it back to normal

ecg_d = double(bi2de(ecg_b));

divide it by 2^32

ecg_d = ecg_d/2^32; 

Now the signal you ve is normalized between 0 and 1. to convert it to original range

ecg_d = ecg_d*norm_1;
ecg_d = ecg_d+shift_up;

[Kumari Surbhi]

It is working fine. Thank you.