The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 07, 1999
Filed:
Sep. 19, 1997
Michael J DeLuca, Austin, TX (US);
Emilio J Quiroga, Lake Worth, FL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A digital demodulator (100) for use in a communication device comprising a mixer (110) which samples a limited IF signal derived from a received radio frequency (RF) signal at a rate less than a Nyquist rate of the limited IF signal and generates a resulting IF signal. A continuous integrator (130) is connected to the mixer (110) and integrates the resulting IF signal over a predetermined number of samples thereof to generate a numerical value representative of a modulation frequency of a limited IF signal. An adaptive peak-valley bit slicer (150) is connected to the continuous integrator (130) and compares each numerical value with a peak threshold, a valley threshold and a mid threshold and generates most-significant-bit (MSB) and least-significant-bit (LSB) values for each sample. The adaptive peak-valley bit slicer (150) adjusts the peak and valley thresholds for use in determining a level of a current numerical value based on the LSB and MSB values determined for a prior sample of the numerical value.