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:
Aug. 14, 1984
Filed:
Oct. 06, 1981
Smith A Rhodes, Falls Church, VA (US);
Communications Satellite Corporation, Washington, DC (US);
Abstract
An apparatus for providing coherent detection of a series of data bursts without a preamble by providing a reference waveform which has the same frequency as the carrier for a received TDMA/MPSK transmission, but having an arbitrary phase with respect to such signals. The reference waveform is used for pseudo-coherent demodulation. Symbol timing is available at all times by using symbol synchronization obtained from the previous bursts of the same transmission. The symbol timing is used to sample two quadrature outputs of the pseudo-coherent demodulator once per MPSK symbol interval. Storage of a sufficient number of demodulator samples allows a carrier phase estimate to be obtained from the message burst itself. The carrier phase estimate is then used for coherent detection on a delayed sequence of the demodulator samples.