Resources Contact Us Home
Demodulator for sampled data FM signals

Image Number 4 for United States Patent #4910469.

A sampled data FM demodulator samples the FM signal at intervals of (2n.pi.+.pi./2) radians relative to the FM carrier. Pairs of samples S.sub.n and S.sub.n+1 are square and multiplied together to generate sample values S.sub.n.sup.2, S.sub.n+1.sup.2 and S.sub.n S.sub.n+1. These sample values are lowpass filtered in a filter having a cutoff frequency which substantially attentuates at least the second harmonic of the FM carrier. The low pass filtered samples are then combined according to the relation S.sub.n S.sub.n+1 /.sqroot.S.sub.n.sup.2 S.sub.n+1.sup.2 to generate demodulated output samples.

  Recently Added Patents
Method for the treatment, alleviation of symptoms of, relieving, improving and preventing a cognitive disease, disorder or condition
Digital processing method and system for determination of optical flow
Liquid crystal panel and liquid crystal display
System and method for oscillator frequency control
Photographic printing paper and method of making same
Image forming apparatus and control method therefor
Controlling transmission resources in mobile radio systems with dualtransfer mode
  Randomly Featured Patents
Method and apparatus to digitize pressure gauge information
Method for providing a power inductor
Device for imparting distance information
Size adjustable athletic boot
Compact disc case wrapper opener
Light scanning apparatus, latent image forming apparatus and image forming apparatus
Deflection apparatus for a conveying system
Reagents for enzyme immunoassay for apolipoprotein B
Tropical fish egg incubator
Underground-environment simulator