[Discuss-gnuradio] Format and dimension of USRP output samples

[Marco Bottino]

Hello everybody,

I'm sorry to post once again a question about the dimension and the format of
the samples output by the USRP, but it is actually hard for me to understand.

I'm using the USRP Motherboard with a LFRX daughterboard.
Question: if the ADC has 12 bits, each sample that arrives from the
doughterboard is 12 bits real or imaginary. But over the USB the samples (real
or imaginary) are 16 bit signed integer. If my resolution is 12 bits, why do I
need 16 bits?
Moreover, using a program like Baudline, the format of the samples I have to use
is complex 32 bits floating point. If they are integer, why floating?

Thank you very much,

kind regards,

Marco