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. 15, 1985
Filed:
May. 26, 1982
Gary D Martin, Andover, MA (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A technique for maintaining frame synchronization in a OAM system transmitting nondifferentially encoded data is disclosed. In accordance with the present invention, multibit words (F.sub.I, F.sub.Q) comprising framing bits are formed and inserted into the transmitter data channels. The value of the framing bit is insensitive to the rotational effects of phase ambiguity by having a predetermined value and by being inserted within a predetermined bit position in each data channel. In the disclosed embodiments, regeneration errors can also be corrected by the transmission of predetermined quadrant bits within the multibit words. In addition, the spectral tones generated by multibit word transmission can be reduced by the use of utility bits in the multibit words.