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. 06, 1999
Filed:
Jun. 27, 1996
David N Hoogerwerf, Everett, WA (US);
David M Stanhope, Tacoma, WA (US);
Cellular Technical Services Company, Inc., Seattle, WA (US);
Abstract
A system and method for collecting fingerprint reference wave forms under controlled conditions includes a radio frequency (RF) enclosure designed to receive a cellular telephone. A control system, including a transmitter and receiver provides RF communications with a cellular phone placed in the enclosure. A processor controls operation of the transmitter and receiver. The processor sends commands to the cellular phone in the enclosure using the transmitter. The transmitted commands are selected to elicit a RF transmission from the cellular phone in response to the command. The receiver detects the response from the cellular telephone and generates a reference wave form indicative of the transmission characteristics of the transmitter of the cellular phone in the enclosure. The processor captures one or more reference waveforms that can be used to generate a fingerprint indicative of a transmission characteristic of the transmitter of the cellular telephone. In addition, the system can include an external power supply and temperature control system to vary the voltage level of power supplied to the cellular telephone in the enclosure and to vary the temperature in the enclosure. By varying the operating voltage and temperature, the processor can collect reference waveforms under a variety of operating conditions. In addition, the processor can select the carrier frequency for the cellular telephone and for the transmitter and receiver of the control system. Furthermore, the processor can vary the transmit power of the system transmitter and the transmit power of the transmitter within the cellular telephone itself. The system is sized to be readily moved from one location to another to permit the simple collection of reference waveforms under a variety of controlled conditions.