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:
Jan. 10, 2006
Filed:
Nov. 13, 2000
John Didomenico, Tucson, AZ (US);
Craig S. Rendahl, Marana, AZ (US);
James Johnson, Tucson, AZ (US);
John DiDomenico, Tucson, AZ (US);
Craig S. Rendahl, Marana, AZ (US);
James Johnson, Tucson, AZ (US);
Environmental Systems Products Holdings Inc., East Granby, CT (US);
Abstract
A remote emissions sensing system is provided with NOdetection capability. First, a reading of the ambient NOconcentration is taken just prior to each vehicle passing through the system. This measurement accounts for any ambient NOconcentration that may be lingering from the exhaust of a previous vehicle. Next, the system takes a blocked reading when the vehicle is located in the path of the beam. This reading accounts for any ambient or system noise that may exist. Finally, the system takes a reading of the exhaust plume as the beam passes through the plume. A processor determines the portion of the reading due to the exhaust plume by subtracting the ambient and blocked readings from the exhaust plume reading. As a result, a more accurate exhaust concentration reading is provided. Additionally, the system may process exhaust plume readings only in a predetermined wavelength band associated with the known absorption spectrum of NOso that data points for which there is no significant absorption of NOmay be eliminated. Thus, any noise or other interference in the non-absorptive wavelengths are minimized. Also, changes in the intensity of the radiation are compensated by subtracting a baseline intensity from each signal.