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
Lighting apparatus
Charged entities as locomotive to control motion of polymers through a nanochannel
Methods and systems for allocating a USB device to a trusted virtual machine or a non-trusted virtual machine
Systems with cooperating reruckers for producing encased products and related rerucker assemblies
Dimethyl-benzoic acid compounds
Aliphatic polyester resin and a process for producing it
  Randomly Featured Patents
Method for smelting reduction of iron ore
Stepping actuator
Electronic processing system
Brushless electric motor, particularly for direct driving of a washing machine
Pyrrolidine and thiazole derivatives with metallo-beta-lactamase inhibitory properties
Device for preventing the jamming of a disc mower by, or the breaking up, a layer of soil and plant matter
Motion vector searching method using plural search areas
Squeeze actuated hand interface systems for rotatable items
Mobile communication terminal
Method of forming an embossed pattern