[USRP-users] calibration on Wifi bands for X310/UBX

Sanjoy Basak sanjoybasak14 at gmail.com
Mon Jul 3 13:20:24 EDT 2017


Hi Derek,
I am referreing to phase calibration. I am taking one transmit signal
(sine/cosine wave) from one x310 and distributing the signal through a 1x4
power divider and feeding it to 4 receivers of 2 other X310s. All the X310s
are connected to the octoclock. Afterwards I am comparing the phase of 4 RX
signals.

For calibration, I take one rx signal as the reference signal and find the
phase differences of other 3 rx signals compared to the reference signal. I
save the offset (initial) phases and use it further for calibration.

As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find the phase
calibration remains even after restarting (or retuning) the USRP. However,
for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the phase
calibration does not remain. After retuning, I find the calibration is
gone.

I also used set_command_time method. But the result was the same.

Best regards
Sanjoy



  <https://mailtrack.io/> Sent with Mailtrack
<https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22>

Sanjoy Basak
Researcher
Royal Military Academy
Dept. Communication, Information Systems & Sensors (CISS)
30, Avenue de la Renaissance
B-1000 Brussels
BELGIUM
Tel : +32-2441 4162
email: Sanjoy.BASAK at mil.be

On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel at ettus.com> wrote:

> Hello Sanjoy,
>
> What calibration are you referring to? Frequency, amplitude, phase? How
> are you doing your calibration and how are you checking it? The more you
> can tell us about your method and the results you are seeing the better we
> can answer.
>
> Regards,
> Derek
>
> On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users <
> usrp-users at lists.ettus.com> wrote:
>
>>
>> Hello Experts,
>> I am trying to calibrate X310/UBX on the whole wifi bands (the complete
>> 2.4 GHz band).
>> 2.412,2.417,2.422,....,2.484 GHz
>>
>> I am doing direction finding tests and need to calibrate 4 channels of 2
>> X310s on the specified frequencies. Both X310s are connected with
>> Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5
>> GHz. For other bands, calibration does not remain after retuning. Is there
>> any specific reason why the calibration only works for every 50 Mhz channel
>> after retuning. I tested with different sampling rates, but the result is
>> the same. Calibration does not remain after retuning.
>>
>> I am using UHD_003.009.002 (installed from synaptic) and ubuntu 16.04. Is
>> there any specific way how I can make it work?
>>
>> Best regards
>> Sanjoy Basak
>>
>>
>>
>>   <https://mailtrack.io/> Sent with Mailtrack
>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22>
>>
>> _______________________________________________
>> USRP-users mailing list
>> USRP-users at lists.ettus.com
>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20170703/aa1f61e6/attachment-0002.html>


More information about the USRP-users mailing list