Hello Andy,
First of all I would like to know which frequency range you want to measure.
What do you understand as high frequency? Several GHz or only a few hundred kHz?
No matter what frequency, you always need an analog to digital conversion to be able to analyse the measured data with PC Technology.
For lower frequencies you can use a data-acquisition board or digitizer (scope) board. These products exist in PCI format.
For higher frequencies (up to several Ghz), the original signal will always be 'downconverted' before it can be analysed No matter if you use a stand-alone desktop instrument or modular solution, they all have a component in it which will bring the original down to a lower frequency which can by analysed.
An example of a downconverter is the NI PXI-5600 (http://sine.ni.com/nips/cds/view/p/lang/fr/nid/11535).
So, to help you find a solution, we first need to know of what frequency range you need to analyse the spectrum of.
Please contact you local NI Branch Office. They can help you find the best solution for your needs.
For Belgium you can reach them on 02 757 00 20.
Best regards,
Spacetronics
Best regards,
Joeri
National Instruments
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