How to generate .iq file from matlab

Quote from eric.velez on 06/11/2024, 18:30

I'm trying to generate a .iq file from matlab and import into the file source block in the aaronia rtsa suite. I do it like the following.

% Parameters
% f = 1000000; % Frequency of the sine wave (Hz)
f = 1; % Frequency of the sine wave (Hz)
% fs = 100000000; % Sampling frequency (Hz)
fs = 100; % Sampling frequency (Hz)
T = 1; % Duration of the signal (seconds)
t = 0:1/fs:T-1/fs; % Time vector

% Generate I and Q streams
I = sin(2 * pi * f * t); % In-phase component (sine wave)
Q = cos(2 * pi * f * t); % Quadrature component (cosine wave)

% Plot the sine wave (I) and cosine wave (Q)
figure;
subplot(2, 1, 1);
plot(t, I);
title('In-phase (I) Component');
xlabel('Time (s)');
ylabel('Amplitude');

subplot(2, 1, 2);
plot(t, Q);
title('Quadrature (Q) Component');
xlabel('Time (s)');
ylabel('Amplitude');

% Generate complex IQ signal
IQ_signal = I + 1i * Q;

% Plot the complex IQ signal on a polar plot
figure;
plot(real(IQ_signal), imag(IQ_signal));
title('IQ Signal (Complex Plane)');
xlabel('In-phase (I)');
ylabel('Quadrature (Q)');

Isig=real(IQ_signal);
Qsig=imag(IQ_signal);

Isig_single =single(Isig);
Qsig_single =single(Qsig);

Iqdata = reshape([Isig;Qsig],[],1);

% Open a file for binary writing
fileID = fopen('\sine_test_float32.iq', 'wb');
% Check if the file opened successfully
if fileID == -1
error('Failed to open the file.');
end

% Write the IQ data to the file
% Here, we assume single precision (32-bit) for both I and Q components

% quack = "quack";
% fwrite(fileID, [quack], 'float32');

% fwrite(fileID, Iqdata, 'int8');
% fwrite(fileID, Iqdata, 'int16');
% fwrite(fileID, Iqdata, 'int32');
% fwrite(fileID, Iqdata, 'float64');
fwrite(fileID, IQ_signal, 'float32');
% fwrite(fileID, Iqdata, 'float32');
% fwrite(fileID, [Isig; Qsig], 'float32');
% fwrite(fileID, [Isig_single; Qsig_single], 'float32');

% Close the file
fclose(fileID);
disp('IQ data has been written to output.iq');

I am able to create a .iq file. When i import the .iq file into the file source block i'm getting "Block 'file source' in critical state. File read error. Am i creating the .iq file incorrectly? Is the format incorrect? Any help would be appreciated.