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. 02, 1990
Filed:
Oct. 26, 1988
Paul D Cole, Fairfield, CT (US);
General DataComm Inc., Middlebury, CT (US);
Abstract
An encoder is provided for generating rotationally invariant trellis codes when used with a signal constellation having m subconstellations indexed by j, each subconstellation having a plurality of points, where each subconstellation is a distinct rotation by j(360/m) degrees of another subconstellation such that no subconstellation has a point in common with another subconstellation. The encoder has a state block and a state update block. The state means receives q inputs i, and generates m outputs j, where m=pq and where p and q are integers greater than one and have no common factors. Outputs m are generated according to inputs i and states s of the state block according to j=i mod q and jd=s mod p, where the state block can assume n states, and n=md where d is an integer greater than one and has no common factors with p. The state update block updates the state block to a new state t chosen from the allowable n states based on the output j and previous state s according to t=jd+F(s-jd) mod n, where F is the permutation of 0, . . . , n-1, and is a function given by F(am+b)=bd+a for a=0, . . . , d-1, and for b=0, . . . , m-1.