Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Methods and apparatus for encoding information in a signal by spectral notch modulation










Image Number 5 for United States Patent #7746939.

A spectral notch modulation technique for encoding information in a signal involves transforming the signal into the frequency domain via a fast Fourier transform (FFT) of length N, such that the signal is represented by N frequency bins, selectively nulling M of the N frequency bins, where nulled combinations of M frequency bins respectively correspond to encoded information bits, transforming the selectively nulled signal to the time domain via an inverse FFT, and transmitting the selectively nulled signal. At the receiving end, the signal is demodulated to recover the encoded information by transforming the signal into the frequency domain via a fast Fourier transform (FFT) of length N, identifying the set of M nulled frequency bins among the N frequency bins, and converting the set of M nulled frequency bins to corresponding information bits.








 
 
  Recently Added Patents
Systems and methods for providing a shared folder via television
Method and apparatus for generating soft bit values in reduced-state equalizers
Ionic compound, anti-static pressure-sensitive adhesive and polarizer comprising the same
Dimmable LED light fixture having adjustable color temperature
Motion estimation for a video transcoder
Distributive data capture
System and method for enhancing buyer and seller interaction during a group-buying sale
  Randomly Featured Patents
Wall panel
Exhaust component of gas exhaust line
Suction nozzle hood for a floor care appliance
Method and device for maintaining a constant pH value of a medical liquid during the dispensing thereof from a container
Magnetic bearing utilizing brushless generator
Quick connect snow plow implement
Transfer device in a metal-forming machine, particularly a transfer press
HARQ operation method for retransmitted data
Communication apparatus, communication system and method of the same
Semiconductor saturable absorber mirror