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:
Dec. 16, 1986
Filed:
Jun. 25, 1985
Applicant:
Inventor:
Thomas Armstrong, Clearwater, FL (US);
Assignee:
Paradyne Corporation, Largo, FL (US);
Primary Examiner:
Int. Cl.
CPC ...
H04J / ; H04L / ;
U.S. Cl.
CPC ...
375 39 ; 3701101 ; 3701104 ;
Abstract
A method of adding a secondary channel to a QAM signal mapped in the complex plane is provided. A pair of positions in the mapped complex plane is determined such that one-half the sum of the square of the distances to such positions from the origin is no greater than the square of the distance from the origin to the position of the furthest mapped data point. For secondary channel communication, a data point is shifted from a normal position to one or the other of the new positions with one of said positions assuming a binary '1' for the secondary channel and the other of said positions assuming a binary '0'.