Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Digital FSK demodulator










Image Number 14 for United States Patent #4825452.

The present invention provides a digital frequency shift keying (FSK) demodulator circuit which receives a hard-limited FSK input signal and recovers the modulating baseband signal at 300 baud or less. The FSK demodulator includes a digital phase locked loop demodulator section which receives the FSK input signal and generates a pulse width modulated output the frequency of which is a function of the input signal frequency. The output of the PLL demodulator section is provided to a quantizer which generates a set of parallel numbers. A translating means, for example a code linearizer, converts the parallel numbers into corresponding parallel outputs which are representative of the frequency of the FSK input signal. The parallel outputs are processed by a digital filter which emulates a second-order, low-pass filter. The filter processes the parallel outputs utilizing pulse density modulation. A deglitcher removes noise from the filter output to provide the demodulated data output.








 
 
  Recently Added Patents
Method for repairing or replacing damaged tissue
Group control method for machine type communication and mobile communication system using the method
Tap and linking module TDO register, gating for TCK and TMS
Hybrid fin field-effect transistor structures and related methods
Developing device
Portable computer
Base station device and wireless communication method
  Randomly Featured Patents
Image recording apparatus
Coiled insect fumigant
Catheter track and catheter for diagnosis and treatment
Method and apparatus for time-shared processing of different data word sequences
Shift register, data line driving circuit, scanning line driving circuit, electro-optical device, and electronic apparatus
Printing mechanism for dot matrix printers
Hybrid tea rose plant named Ruirovingt
Dynamic time series prediction of traffic conditions
Femur component for an artificial hip joint
Motor apparatus