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:
May. 02, 2000
Filed:
Jun. 11, 1997
Abstract
A synchronization system and method for obtaining frame, carrier, and sampling synchronization of an input OFDM modulated digital signal having a pseudoperiodic second symbol. The system includes an apparatus for obtaining frame synchronization, and the apparatus includes an envelope detector to detect the first symbol of the input signal, and a differentiator connected to the envelope detector to detect the second symbol. The differentiator includes a first filter having a transfer function H(z)=(1+z.sup.-1) and a second filter having a transfer function H.sub.p (z)=(1-z.sup.-n/2 +z.sup.-n -z.sup.-3n/2), where n equals to a number of samples in the input signal. Synchronization of the carrier frequency offset is obtained by first obtaining the fractional carrier frequency offset, and then obtaining the integral carrier frequency offset through a matched filtering process. Sampling frequency synchronization is obtained through the matched filtering process for determining integral carrier frequency offset.