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:
Oct. 16, 2001
Filed:
Aug. 24, 1998
Veit Armbruster, St. Georgen, DE;
Claus Muschallik, München, DE;
Deutsche Thomson-Brandt GmbH, Villingen-Schwenningen, DE;
Abstract
In an OFDM system, the so-called self-noise component, which represents that noise component of the respective carrier which is caused by the carrier itself and is mapped onto itself, can be estimated and corrected by shifting all the carriers back in the receiver by multiplication by a factor which is determined by averaging. The so-called external-noise component, which is caused by adjacent carrier interference from the so-called leakage effect of the Fast Fourier transform (FFT,) used in the receiver for demodulation cannot be corrected using this method. In addition to the demodulation FFT, a further FFT (FFT,) is used in the receiver to estimate the self-noise component (&psgr;,). The estimated self-noise component is used to reproduce the orthogonality between the carriers by correction before the demodulation FFT, to thereby prevent crosstalk. The additional FFT (FFT,) may have a shorter length than the demodulation FFT (FFT,), so that the additional complexity is negligible.