摘要 |
A FM (Frequency Modulated) DCFB (Deviation Compression Feedback) signal demodulator can be achieved by utilizing FM deviation compression feedback techniques. An FM signal is coupled to a mixer (10) wherein a signal from a local oscillator is mixed with the input signal. The output of the mixer is then coupled to a variable selective IF amplifier. The IF amplifier couples the signal to a limiter amplifier, the output of the limiter amplifier is FM demodulated and fed to an output. The output signal is simultaneously fed back through a variable Frequency Compensation Network (FCN) (Loop Filter). The output signal of the FCN is then fed back to a local oscillator (17). The output of the local oscillator (17) is in turn fed back into the original mixer (10). The improved demodulated signal is sampled at an output (26).
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