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. 29, 2003
Filed:
Nov. 19, 1998
Legerity, Inc., Austin, TX (US);
Abstract
A signal detector for detecting at least a first signal having a first frequency includes a matched transform unit and an energy level threshold unit. The matched transform unit is adapted to receive at least a first frame of time domain input samples at a sampling frequency and generate at least a first frequency energy value for the first frame based on at least a first subset of the time domain input samples and a first matched filter coefficient. The sampling frequency is a non-integral multiple of the first frequency, and the first matched filter coefficient depends on the first frequency. The energy level threshold unit is adapted to compare the first frequency energy value to a threshold energy value to determine the presence of the first signal. A method for detecting at least a first signal having a first frequency is provided. The method includes receiving at least a first frame of time domain input samples at a sampling frequency. At least a first frequency energy value for the first frame is generated based on at least a first subset of the time domain input samples and a first matched filter coefficient. The sampling frequency is a non-integral multiple of the first frequency, and the first matched filter coefficient depends on the first frequency. The first frequency energy value is compared to a threshold energy value to determine the presence of the first signal.