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:
Jun. 24, 2008
Filed:
Apr. 06, 2004
Adrian Andrew Dorrington, Hamilton, NZ;
Adrian Andrew Dorrington, Hamilton, NZ;
The University of Waikato, Hamilton, NZ;
Abstract
The invention relates to a solid-state range sensing system. As with previous solid-state range sensing systems, an energy source is activated and deactivated in a cyclic pattern with a selected source frequency. A receiver is adapted to sense the reflection of emitted energy from the target. The receiver includes a shielding system to block the sensing of the reflected energy from the target in a cyclic pattern with a selected receiver frequency. Unlike the prior art, the frequency of the source and receiver are offset by a small frequency. The resulting output signal of the receiver is a further cyclic pattern beat signal of frequency equal to the difference between the source activation and receiver shielding modulation frequencies. The best signal is effectively a down-converted version of the source modulation frequency and, unlike the prior art, is compared with a reference beat signal whereby the phase difference between the two beat signals is used to determine a range value. The use of beat signals provides higher precision than the prior art.