Difference in gain using gnuradio 3.1.3 and the trunk (at least on RFX1800)


#1

Dear All,

I have connected a signal generator to my USRP and I am using a CW. Thus
I
have a constant input power. I am running the usrp_rx_cfile.py utility
(exact command line below). If I run gnuradio 3.1.3 then the amplitude I
see
is 16dB higher than if compile from the trunk (checked out a week ago
or
so). I think it has to do with the new daughterboard code being
different
from the old python one. I am using an RFX1800 daughterboard.

The signals are also conjugated with respect to each other

BR/
Per

sudo ./usrp_rx_cfile.py -d 8 -f 1902.5e6 -R A -s -g 50 -N 5000 test.dat


#2

On Wed, Apr 1, 2009 at 11:45 PM, Per Z.
removed_email_address@domain.invalid wrote:

I have connected a signal generator to my USRP and I am using a CW. Thus I
have a constant input power. I am running the usrp_rx_cfile.py utility
(exact command line below). If I run gnuradio 3.1.3 then the amplitude I see
is 16dB higher than if compile from the trunk (checked out a week ago or
so). I think it has to do with the new daughterboard code being different
from the old python one. I am using an RFX1800 daughterboard.

In other words, the magnitude of the samples in the captured .dat
files are different by a factor of 16dB? Do they otherwise look the
same spectrally?

The signals are also conjugated with respect to each other

Conjugated, as in a+bi => a-bi , or as in a+bi => b+ai?

Johnathan