Theoretical questions

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Theoretical questions

Post by shaimaor » Wed Mar 17, 2021 4:20 pm

What is the meaning of sample sync and calibrate IQ in the device's app?
What is the meaning of the value "100" FIR tap size? what does it mean "how tight the filter is"?
Why did you set all the antennas gain to 33.8dB?
Thank you in advance!
Shai and Kfir

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Re: Theoretical questions

Post by ckoval7 » Wed Mar 17, 2021 5:31 pm

Are you using a KerberosSDR? Judging by your questions, probably not and you're using the wrong software. If you are, please read through the quick start guide and take your questions to the KerberosSDR section on the forum.

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Re: Theoretical questions

Post by rtlsdrblog » Wed Apr 14, 2021 11:03 am

Please consult the guide at

You need to perform sample and IQ sync first after booting the Kerberos, or after changing frequency. This is to achieve phase coherence.

For FIR filtering, the value is how "tight" or "sharp" the filter is. Basically how rectangular it is.

The gain was set to 33.8 in the examples because that gave the best SNR for the signal I was looking at.

You might want to get familiar with basic DSP concepts and SDRs in general first before tackling the KerberosSDR, as that is a much higher difficulty to master since it's experimental and deals with more advanced ideas.

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