Wideband FM demodulation

[madd]

Hello

Anyone who can guide me about Analog FM wideband signals demodulation.signals are in Bit format recorded using 5600 and 5142 having cctv Video inside. BW about 20MHZ. I have read somewhere there are different types of modulation inside a FM wideband signal. Like QAM for Video (about 4.5Mhz out of 20Mhz),FM for audio and some other for color information. How will I demodulate it to see the Video I have recorded using NI Modulation toolkit.

Regards

[Abhay_Samant]

Hi:

Do you know the spectrum map of the signal?  In other words, where in your 20MHz range, is the video and audio signals.  If this is the case, then you first demodulate the FM signal, and then filter the demodulated baseband signal to just get the video signal and then further demodulate this signal.  I have used this technique in case of RDS signals, where there is a QPSK signal embedded inside the FM signal.