Edges amplitudes the signal in matlab

Dear

When capturing the samples with the following configuration, these amplitudes appear at the edges, what is the reason for this?

dev = limeSDR();
dev.rx0.frequency = 863100000;
dev.rx0.samplerate = 4000000;
dev.rx0.bandwidth = 2000000;
dev.rx0.gain = 0;
dev.rx0.antenna = 3;
dev.rx0.enable;
dev.rx0.calibrate;
dev.start();
[IQ_samples, ~ , actual_count] = dev.receive(10000000,0);

Thank you

It is FFT properties: results are repeated after Fs/2 (sample rate). What you see at the edges are central spike (received local oscillator leakage). If you increase sample rate or decrease badwidth you will lose spikes.

1 Like

@yt7pwr
Thanks for your answer.
I was reviewing the code of the libraries and I eliminated the spikes of the borders with the oversampling options.