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:
Sep. 29, 1992
Filed:
Jun. 22, 1989
Benoit Gelin, Bonneuil, FR;
Michel Lebourg, Marcoussis, FR;
U.S. Philips Corp., New York, NY (US);
Abstract
The method ensures the coherent demodulation by digitally processing a continuous-phase modulated signal (for instance, of the GMSK type). The received signal is transposed in the baseband, converted into a digital signal and transferred to a signal processor. Each transmitted data packet has a known preamble sequence of N bits which allows for approximate estimation of the frame-synchronization and the bit-synchronization and also the initial phase and the residual frequency offset. The progressive refinement of the estimation is obtained with two interleaved digital loops: a slow loop for detecting the bit-synchronization and a fast loop effecting intermediate decisions over additional blocks of bits for the estimation of the initial phase and the residual frequency offset.