wtr
Full Member level 5
Hello,
The picture below is a capture of a FPV drone camera. It's a PAL/NTSC signal. This signal is Amplitude modulated.
I've sampled the continuous wave signal and fed it through an FFT, etc to generate this spectogram.
What concerns me is the fact that the carrier frequency seems to fluctuate. So my questions which i need help with are as follows.
1. Why does it not stay fixed on f_c? Why does it move like an FM signal? Is this because of multipath?
2. See second picture. Why does it work perfectly some times?
Thanks in advance,
Wes
The picture below is a capture of a FPV drone camera. It's a PAL/NTSC signal. This signal is Amplitude modulated.
I've sampled the continuous wave signal and fed it through an FFT, etc to generate this spectogram.
What concerns me is the fact that the carrier frequency seems to fluctuate. So my questions which i need help with are as follows.
1. Why does it not stay fixed on f_c? Why does it move like an FM signal? Is this because of multipath?
2. See second picture. Why does it work perfectly some times?
Thanks in advance,
Wes