Hi guys. I have to compare mixer circuits for demodulation for a uni assignment.
One of the questions asks the average power of the demodulated signal in the 050MHz range, so I built the circuit in LTspice and took the FFT of the demodulated signal. For a trace in the time domain, I can get the average and RMS values by holding Ctrl and clicking on the trace name, but in the FFT it gives a different set of measurements (see attached screenshot).
I've tried googling, but I don't understand how to get the average power over a certain range in the frequency domain. Any help or advice will be greatly appreciated.
Thanks.
One of the questions asks the average power of the demodulated signal in the 050MHz range, so I built the circuit in LTspice and took the FFT of the demodulated signal. For a trace in the time domain, I can get the average and RMS values by holding Ctrl and clicking on the trace name, but in the FFT it gives a different set of measurements (see attached screenshot).
I've tried googling, but I don't understand how to get the average power over a certain range in the frequency domain. Any help or advice will be greatly appreciated.
Thanks.
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