[time-nuts] Very challenging phase noise measurement, does anyone have an idea??

Adrian rfnuts at arcor.de
Thu Dec 6 00:39:59 UTC 2012


You can always use an external mixer / phase detector and the baseband 
input of a HP 3048A or FSUP.

Just to name a few:
For low power (+7dBm) you can use a SRA-3 which goes from 25kHz to 200MHz
SRA-3MH +13dBm from 25kHz to 200MHz
SRA-3H +17dBm from 50kHz to 200MHz
For high power signals use a RAY-3. It goes from 70kHz to 200MHz.
The IF must be specified from DC, which for the above is the case.

Between mixer and baseband input a lowpass filter is required to 
suppress the sum signal (2x f_input) sufficiently.

Adrian


Azelio Boriani schrieb:
> Yes, I have taken a look and the FSUP is 1MHz min at the signal analyzer.
> Timepod? No, 500KHz min... an R&S FAM modulation analyzer?
>
> On Wed, Dec 5, 2012 at 10:48 PM, Bob Camp <lists at rtty.us> wrote:
>
>> Hi
>>
>> A "3048" style measurement with the carrier suppressed by lock should do
>> pretty well. If the XOR's are out, there are a lot of mixers available that
>> work at 125 KHz. A simple op-amp buffer and a sound card could do what you
>> need to do.
>>
>> Bob
>>
>> -----Original Message-----
>> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
>> Behalf Of Adrian
>> Sent: Wednesday, December 05, 2012 4:33 PM
>> To: Discussion of precise time and frequency measurement
>> Subject: Re: [time-nuts] Very challenging phase noise measurement, does
>> anyone have an idea??
>>
>> For phase noise the frequency range is 1MHz to 8/26.5/50GHz
>> The spectrum analyzer works from 20Hz to max.
>>
>> Adrian
>>
>>
>> Azelio Boriani schrieb:
>>> Isn't the FSUP a 110K euros equipment 20Hz-50GHz capable? 125KHz
>> shouldn't
>>> be a problem. I had an FSUP for 25 seconds to play with... really
>>> impressive but too limited test time to appreciate fully.
>>>
>>> On Wed, Dec 5, 2012 at 1:14 PM, Bob Camp <lists at rtty.us> wrote:
>>>
>>>> Hi
>>>>
>>>> Just about any of the high speed CMOS parts should work. A 74AC86 is
>> about
>>>> the earliest part I would trust. Any of the fast logic families that
>> came
>>>> after that should do equally well.
>>>>
>>>> Bob
>>>>
>>>> On Dec 5, 2012, at 7:03 AM, Hans Rosenberg <Hrosenberg at catena.nl>
>> wrote:
>>>>> Hello Time-nuts,
>>>>>
>>>>> I have to do a phase noise measurement and I'm wondering if anyone here
>>>> has any ideas on that. We have to measure the phase noise of a 125kHz
>>>> carrier (5Vp-p signal level). The measurement system should have a noise
>>>> floor that is -164dBc/Hz at a distance of 1kHz to 8kHz away from the
>>>> carrier.
>>>>> Our current plan is to use 2 of these sources, have one in free running
>>>> mode and lock the other one to the first one using an XOR gate and then
>> use
>>>> the output of the XOR gate as an output signal. However, we are
>> wondering
>>>> if any of you know a better idea. Maybe there is an off-the-shelf piece
>> of
>>>> equipment that can do that that we could rent. Or maybe we could
>> increase
>>>> the frequency to a few megahertz using a pll, which means the signal
>> comes
>>>> into the measurement range of our FSUP phase-noise analyzer. Problem is,
>>>> the phase detector would then need to have an insanely low noise-floor
>> (in
>>>> our idea the XOR also has to have this insanely low noise floor as well
>> off
>>>> course) so does anyone have experience with anything like this? Does
>> anyone
>>>> know an XOR with these good specs? I don't have a clue what a standard
>>>> 74lvc1g86 would do. Needless to say the supply of this XOR would have to
>> be
>>>> ridiculously clean, but I do have a solution for that problem.
>>>>> Any help is greatly appreciated!
>>>>>
>>>>> Best regards,
>>>>>
>>>>> Hans Rosenberg
>>>>> _______________________________________________
>>>>> time-nuts mailing list -- time-nuts at febo.com
>>>>> To unsubscribe, go to
>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>>> and follow the instructions there.
>>>> _______________________________________________
>>>> time-nuts mailing list -- time-nuts at febo.com
>>>> To unsubscribe, go to
>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>> and follow the instructions there.
>>>>
>>> _______________________________________________
>>> time-nuts mailing list -- time-nuts at febo.com
>>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> and follow the instructions there.
>>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>>
>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>




More information about the time-nuts mailing list