Hello Abhilash,

Also, please consider using QT gui instead of WX. That has nothing to do
with this issue, however. WX GUI components are no longer supported and
will be dropped in near future.

Regards,
Kyeong Su Shin

On Sat, Feb 3, 2018 at 9:42 PM, Kyeong Su Shin <kss...@uw.edu> wrote:

> Hello Abhilash,
>
> That is because the power level is relative. Unless you use a absolute
> power level (dBm/Hz, etc), the comparison of the power level magnitude is
> meaningless. The spectrum analyzer is probably giving you dB'm' readings,
> but the USRP is not.
>
> You cannot get absolute power level readings from USRPs unless you
> calibrate them amplitude-wise (by yourself). Even then, USRP is not a
> perfect replacement of a spectrum analyzer (generally better than cheaper
> SDRs, though).
>
> Regards,
> Kyeong Su Shin
>
>
>
> On Fri, Feb 2, 2018 at 2:39 PM, abhilash b <abhilash2...@gmail.com> wrote:
>
>> Hello,
>> I am using USRP N210 with CBX daughter board.
>> In the GNU radio I use USRP_source block followed by wx_gui_fft sink
>> block. I input a power of -60dB to the USRP.  The input power is measured
>> using a spectrum analyzer.
>>
>> The RF gain in the source block is kept at 0 dB, sample rate of 25 MHz
>> and center freq of 2.4 GHz
>>
>> But the fft block shows the power to be -40dB.
>> Could you please tell me why such a huge offset.
>>
>> --
>>
>>
>> -Regards
>> Abhilash B
>>
>>
>>
>> _______________________________________________
>> Discuss-gnuradio mailing list
>> Discuss-gnuradio@gnu.org
>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>
>>
>
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

Reply via email to