svensl
Full Member level 1
Hello,
When using an IDEAL VCO in VerilogA to generate a frequency modulated signal, then the instantaneous frequency of that signal is proportional to the modulating input signal. When using VerilogA to measure the period of the FM signal and thus finding the frequency I can sample these values and export them to Matlab to do an FFT.
My question is regarding the noise floor. The maximum SNR I can get is somewhat in the range of 90dB for a given VCO gain and input amplitude. Why only so little? What determines the noise floor as everything is ideal and I am not introducing any quantization either?
Any ideas?
Thanks for your thoughts.
svensl
When using an IDEAL VCO in VerilogA to generate a frequency modulated signal, then the instantaneous frequency of that signal is proportional to the modulating input signal. When using VerilogA to measure the period of the FM signal and thus finding the frequency I can sample these values and export them to Matlab to do an FFT.
My question is regarding the noise floor. The maximum SNR I can get is somewhat in the range of 90dB for a given VCO gain and input amplitude. Why only so little? What determines the noise floor as everything is ideal and I am not introducing any quantization either?
Any ideas?
Thanks for your thoughts.
svensl