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:
Mar. 25, 2008
Filed:
Dec. 17, 2003
Wolfgang Schott, Rueschlikon, CH;
Pedro E. Coronel, Thalwil, CH;
Simeon Furrer, Adliswil, CH;
Jens Jelitto, Rueschlikon, CH;
Beat Weiss, Edlibach, CH;
Dietrich Maiwald, Waedenswil, CH;
Wolfgang Schott, Rueschlikon, CH;
Pedro E. Coronel, Thalwil, CH;
Simeon Furrer, Adliswil, CH;
Jens Jelitto, Rueschlikon, CH;
Beat Weiss, Edlibach, CH;
Dietrich Maiwald, Waedenswil, CH;
International Business Machines Corporation, Armonk, NY (US);
Abstract
The present invention discloses a method and apparatus for adjusting gain setting, receiver clock frequency, and symbol timing in an OFDM radio receiver. The method is based on the reception of a preamble with known periodic training sequences transmitted prior to user data over the radio channel. By computing a periodicity metric, an inner receiver detects the presence of periodic signals in the received data sequence, provides means to set the Variable Gain Amplifier VGA gain in the radio frontend, and estimates frequency offsets between the transmit and receive clock. Matched filters are used to determine the symbol timing. A finite-state-machine schedules various tasks during the receiver startup.