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. 23, 1986
Filed:
Apr. 01, 1985
James L Snell, Palm Bay, FL (US);
Harris Corporation, Melbourne, FL (US);
Abstract
A technique for deriving a phase reference for PSK demodulation uses the absolute values of phase vectors as they are received to establish a reference with which the individual phase vectors are compared for data demodulation. Over some span of N successively received signals (phase vectors), the received phase vectors are successively analyzed to derive a hypothetical reference phase vector with which the vector symbols are to subsequently compared for data demodulation. The symbol values are temporarily buffered as they are received. As each phase vector is received, all possible (i.e. M-ary) phase values, referenced to the value of the received phase vector, are compared to a stored reference. Each of these M-ary possible phase values is vector-summed with the stored reference and the resulting vector sum having the largest magnitude is then substituted for the stored reference and is used by the next received vector symbol to further refine the reference vector. This process is carried out successively for each of the received phase vector of the N-symbol span, at the completion of which the successively refined value of the stored reference vector is used to demodulate the previously received and buffered N symbols of the span of interest.