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:
May. 28, 1996
Filed:
Feb. 10, 1994
Gary T Carroll, Boulder, CO (US);
J Donald Pauley, Estes Park, CO (US);
Michael X Bond, Boulder, CO (US);
Racom Systems, Inc., Englewood, CO (US);
Abstract
A passive transponder incorporating non-volatile ferroelectric memory is powered by inductive coupling to a proximately located controller. A communication system and method utilizes the controller to send data and commands to the transponder by an FSK modulated RF signal in order to cause the transponder to either read selected data from, or write selected data to, the non-volatile memory and transmit the same back to the controller utilizing PSK RF modulation. The communication system and method operates either full duplex or half duplex with the controller causing the transponder to simultaneously write data to its non-volatile memory as the memory is read out and transmitted to the controller thereof. Features of the invention include, signal transmission between the controller and transponder occur concurrently; the controller's FSK signal is modulated between 125 KHz and 116.3 KHz; the transponder's PSK signal is 62.5 KHz; the controller formulates a digital message that includes the address of information stored in the transponder, synchronization bits, and command bits; the controller's digital message is detected by the transponder and causes the transponder to read its data information and then transmit a signal back to the controller that is modulated with the data information; the controller's digital message includes a complement signal that is transmitted coincident with each bit of the transponder's data information to be changed; and the controller's digital message includes a memory address whereby blocks of transponder data information are read, beginning with this address.