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. 01, 2003
Filed:
Jan. 20, 1999
Thomas Guthrie Zimmerman, Cupertino, CA (US);
Richard Clement Allen, Los Gatos, CA (US);
David Jun Lu, San Jose, CA (US);
Florian Vogt, Hamburg, DE;
International Business Machines Corporation, Armonk, NY (US);
Abstract
Systems and methods for optimizing performance of personal area network (PAN) systems that use electric fields as communication media between PAN transmitters carried by people and PAN receivers mounted on computers to which selective access is sought to be established. Multiple PAN receiver antennae are mounted on a keyboard, such that if a person with a PAN transmitter rests her arms on or near the keyboard, sufficient signal from the transmitter is sensed by one or more of the receiver antennae even though some of the signal is shunted away from the receivers through the arms. Also, a driven shield insulates a PAN receiver from nearby metal objects, e.g., a desk on which the PAN receiver is supported. Moreover, a multiple-electrode PAN transmitter reduces the deleterious effects on the signal from the PAN transmitter that can otherwise be caused by, e.g., loose metal coins that are present in a pocket in which the transmitter is carried. Further, differential receive electrodes prevents undesirable coupling of a PAN transmitted signal to a computer's receiver through a person who has positioned herself between the receiver and the person carrying the PAN transmitter to, for example, gain unauthorized access to the computer.