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. 17, 2004
Filed:
Feb. 25, 2002
Dan Avidor, Ocean, NJ (US);
Colin Alan Warwick, Holmdel, NJ (US);
Agere Systems, Inc., Allentown, PA (US);
Abstract
A frequency and phase estimator simultaneously estimates the frequency and phase of an MPSK modulated signal with a frequency uncertainty range on the order of the symbol rate. The estimator defines a plurality of contiguous bands within the frequency uncertainty range of the signal, estimates the frequency to one of the bands, and utilizes the frequency estimate to derive a phase estimate. In a preferred embodiment, a plurality of signal samples of the frequency shifted signal in each of said bands are accumulated to produce a vector for each band, and the frequency estimate is selected in one of said bands, based upon the magnitude of the corresponding vector. The phase is estimated from the argument of the corresponding vector. The present invention is particularly suited for burst modems or TDMA systems, where frequency and phase estimates must be derived reliably from a limited number of incoming symbols at the beginning of each burst.