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. 12, 2010
Filed:
Nov. 19, 2003
Applicant:
Martin S. Wilcox, Redhill, GB;
Inventor:
Martin S. Wilcox, Redhill, GB;
Assignee:
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04B 1/38 (2006.01);
U.S. Cl.
CPC ...
Abstract
A wireless activation system, such as a keyless car entry system, uses repeated code sequences for communication between a transmitter device and a receiver device. By varying the sequence duration in a synchronism at the transmitter device and receiver device, either by varying the number of symbols or chips in the sequence, or by varying the symbol or chip rate, it is made more difficult for an unauthorised party to detect the code sequences and relay the code sequences to achieve unauthorised activation at the receive device.