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:
Apr. 28, 1998
Filed:
Sep. 16, 1996
Zhijian James Wu, Rochester Hills, MI (US);
John Fiaschetti, Warren, MI (US);
Chrysler Corporation, Auburn Hills, MI (US);
Abstract
The present invention provides a system for detecting and removing resonance from crankshaft speed measurements comprising signal demodulation and deconvolution processing. According to the invention, a crankshaft speed sensor sends an appropriate signal corresponding to crankshaft speed to an engine controller. The input signal with resonance noise is subjected to a demodulation operation in N demodulation subsystems for resonance detection and identification. Also, the input signal with resonance noise is subjected to a deconvolution operation in N deconvolution subsystems for resonance noise removal. The demodulated signals are compared to a given set of criteria for selecting a desired signal subsystem. The desired demodulated signal subsystem is then used to screen the deconvolved signal so that only a matching deconvolved signal exits the system as the system output. Accordingly, the signal from a deconvolved signal subsystem matching the selected demodulated signal subsystem is selected as the system output. By properly identifying the desired signal subsystem during demodulation and suppressing resonance noise during deconvolution, the system output signal has an enhanced signal-to-noise ratio. Hence, the output signal is better suited for further processing, such as engine misfire detection, than according to the prior art.