convert power spectrum back to original waveform

[Jieyi]

Hi,

I have program my PXI 5610 to transmit a sine wave to my PXI 5600.

But when I use the 'ni5660 Read Averaged Power Spectrum VI' to read the signal, it comes out as a power spectrum.. So how can I convert this power spectrum back into my sine wave to show it on the graph.

I am new into this field, hopefully someone can help me out.

Thanks.

[Yardov]

Hello Jieyi,

When you read your signal as spectrum, you loose the phase data. You can still get your signal back but it would not have any information about the phase. I would suggest you acquire the time domain data. This is very simple since the driver can do everything for you.
The time domain data will be automatically converted to In Phase (I) and Quadrature Phase (Q) which are two components that changes the carrier. You can read more about IQ signals here.
Then, you can open the example called ni5660 Getting Started IQ.vi located under "\LabVIEW 8.x\examples\instr\ni5660" and look at this:

Finally, if you have modulation toolkit, you can open any modulation example to transmit a sinewave. These are located at:
"\LabVIEW 8.x\examples\Modulation\RFSG examples"
For example, AM:
Transmitter (Tx)
MT RFSG Generate AM.vi
Receiver (Rx)
MT ni5660 Demodulate AM.vi

These examples are ready to transmit any standard waveform including your sinewave.
Hope these information helps,

Message Edited by Yardov on 08-17-2007 06:50 PM