Frequency to time domain

Dear all,
I've acquired some frequency domain data from PXI-5660 using 'Read average power spectrum.vi' and 'SMT unit conversion'. Now, there is a requirement to convert this data into time domain. I've tried by simply passing this data through an inverse FFT VI but I didn't work. Any advices or suggestions on how I should proceed?
Thanks for the help!
Shazlan

Hi All,
I am working on DAC bench automation.I am sending a digital signal at some sampling frequency to DAC(Digital to analog) board.
The output from the DAC board is connected to Spectrum Analyzer(Agilent E4440A).
Using LabVIEW driver I am able to get the Frequency domain signal in my Graph.
I wanted to calculate the THD,THD+N,SFDR,Harmonics and SNR.Please anybody suggest how i can get these values.I am having below information:-
1. Sampling Frequency
2. The amplitude of the received signal is in dBm and base (X-Axis) is in frequency.
3. Fundamental Frequency.
4. Start Frequency and Stop Frequency.
5. There is the attached sampled data and snapshot of the frequency domain graph.
Thanks.
Ritesh Mishra
Attachments:
SampleFFTData.vi ‏16 KB
FreqDomainPlot.PNG ‏34 KB

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Hi there,
Thanks for your reply
Let me show you respose of BroadBand I have from VNA
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>> StringTheoryNYC wrote:
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StringTheoryNYC wrote:
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It's not mentioned because there's nothing at all wrong with it - as this reply attests...
StringTheoryNYC wrote:
I'm not sure why that would be a 'very strange question' though. 'Brick wall' refers to the sharp transition between pass band and stop band. It's a commonly used term. I prefixed with 'near', since I'd ordinarily moderate the transition to avoid Gibbs phenomenon.
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DateTimeData objects in Forte are inefficient, both in terms of memory
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-----Original Message-----
From: Jones, Kerreck [SMTP:[email protected]]
Sent: Tuesday, January 19, 1999 11:36 AM
To: '[email protected]'
Subject: date-time domain overhead in express queries.
In our application, we have an outline window which displays 11 fields, 3
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35 seconds. Is there any
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Thanks in advance for any info.
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I have considered this but have not found an elegant solution to the
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Scalars take up no 'object space' so you save on garbage collection.
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From: [email protected]
To: [email protected]
Cc: [email protected]
Subject: RE: date-time domain overhead in express queries.
Date: 19 January 1999 18:22
DateTimeData objects in Forte are inefficient, both in terms of memory
footprint and instantiation speed. My understanding is that it stores
different parts of the date as separate textdata sub-objects.. Large
footprint also means they take a long time to pass across the network.
We rarely use DataTimeData or any related "domain" type objects. We have
our own date class which stores the entire date and time in a singlestring
attribute.. Much faster, much smaller footprint, etc. Fetches from the
database use a "to_char(...)" approach to format the date from thedatabase
directly in to the internal string attribute in the correct format, again
for speed..
-Greg
-----Original Message-----
From: Jones, Kerreck [SMTP:[email protected]]
Sent: Tuesday, January 19, 1999 11:36 AM
To: '[email protected]'
Subject: date-time domain overhead in express queries.
In our application, we have an outline window which displays 11 fields,
3
of
which are date time domain.
Our database currently contains about 1500 entries, and the query takesas
long as 70 seconds. If we
remove the DTG domains from the application model, then the query takes
only
35 seconds. Is there any
known problem with the overhead of the express date time domain whendoing
queries?
Thanks in advance for any info.
To unsubscribe, email '[email protected]' with
'unsubscribe forte-users' as the body of the message.
Searchable thread archive<URL:http://pinehurst.sageit.com/listarchive/>
To unsubscribe, email '[email protected]' with
'unsubscribe forte-users' as the body of the message.
Searchable thread archive <URL:http://pinehurst.sageit.com/listarchive/>-
To unsubscribe, email '[email protected]' with
'unsubscribe forte-users' as the body of the message.
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vasus wrote:
Hi,
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