[Discuss-gnuradio] USRP 1 dynamic range

[Sebastiaan Heunis]

Hi everyone

I have a question about the dynamic range of the USRP 1.  Let's say I
have 2 input signals.  The power of the one signal is such that it
uses just about all the dynamic range of the ADC.  How low can the
second signal be in order for both to be detected when they reach the
PC (after DDC and decimation)?  Theoretically this should be around
72dB.

I did a simulation in Icarus where I fed a 6MHz wide chirp signal with
a dynamic range of 72dB into the CORDIC module and looked at the
output.  The output signal only has a dynamic range of around 50dB.
Does this mean that I did something wrong, or could we in fact lose
that much dynamic range in the CORDIC?

Thanks in advance.

Sebastiaan

-- 
Sebastiaan Heunis
Radar and Remote Sensing Group, University of Cape Town
Tel:  +27 83 305 5667