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:
Jan. 26, 1993
Filed:
Dec. 21, 1990
Applicant:
Inventors:
Henry L Kazecki, Arlington Heights, IL (US);
James C Baker, Hanover Park, IL (US);
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04J / ;
U.S. Cl.
CPC ...
3701001 ; 375 56 ; 375 83 ;
Abstract
A differential quadrature PSK receiver (100) recovers serial data in a forward and reverse direction in time using a forward and reverse mode PLL (232) and decoder switch (108). The DQPSK receiver (100) is particularly useful for recovering a packet of serial data (Rx) having a time-varying signal level and a relatively long duration. Sync words in the packet (Rx) or adjacent packets (Ry) provide starting points from which the data is recovered. The direction in time of data recovery is dependent on the quality of the time-varying signal level in the packet (Rx).