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:
Feb. 27, 1996
Filed:
Jan. 04, 1994
Mani Kimiavi, Paris, FR;
Alcatel Telspace, Nanterre Cedex, FR;
Abstract
A device for synchronizing the phase of each packet of a phase modulated digital signal comprises a correction module controlled by information supplied successively by two separate calculator circuits. The phase synchronization device can be integrated into the demodulator stage of a receiver for digital signals phase modulated with at least two phase states, this signal being transmitted by successive packets. The device comprises a corrector module for rotating the constellation of phase states of the received signal according to an indication representative of the angular offset of this constellation. For each received packet to be synchronized in phase, the angular offset indication controlling the corrector module is supplied initially, for a predetermined time, by a first calculator circuit implementing the Viterbi algorithm (first indication) and thereafter, after a switching time corresponding to the end of the predetermined time, by a second calculator circuit constituted by a phase-locked loop (second indication), the second calculator circuit being initialized with the first angular offset indication at the switching time. The device enables fast phase synchronization with good noise immunity.