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. 09, 1997
Filed:
Feb. 28, 1994
Prashant B Thakore, Pittsburgh, PA (US);
ABB Daimler-Benz Transportation (North America) Inc., Pittsburgh, PA (US);
Abstract
A method and apparatus for communicating over a track circuit which includes an interference signal. The invention includes sampling the interference signal on the track circuit at a predetermined sampling frequency to produce a sampled interference signal, detecting interference at a predetermined first sub-carrier frequency based on a fast Fourier transform of the sampled interference signal, forming a vector signal corresponding to a predetermined second sub-carrier frequency related to the predetermined sampling frequency and different from the predetermined first sub-carrier frequency, performing an inverse fast Fourier transformation on the vector signal to form a series communication signal, coupling the series communication signal to the track circuit, sampling the series communication signal on the track circuit at the predetermined sampling frequency from a sampled communications signal, and recovering the vector signal based on a fast Fourier transform of the sampled communication signal.