High-performance mobile power antennas

• US 7,511,621 B1
• Filed: 03/30/2007
• Issued: 03/31/2009
• Est. Priority Date: 08/31/1995
• Status: Expired due to Fees

• Current Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Original Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Inventors: Ruggiero, Lou, Friedman, Daniel J., Duan, Dah-Weih, Bardwell-Jones, Ian, Heinrich, Harley Kent
• Primary Examiner(s): TWEEL JR, JOHN ALEXANDER
• Application Number:
  US11/694,229
• Time in Patent Office: 732 Days
• Field of Search: 340/572.1, 340/572.7, 340/572.6, 340/572.4, 340/10.1, 340/10.34, 340/539, 340/551, 342/27, 342/44, 342/51
• US Class Current: 340/572.7
• CPC Class Codes: G01S 13/758 using a signal generator powered by the interrogation signal
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• CPC Class Codes: G06K 19/0713 the arrangement including a power charge pump
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 21/29 Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence

Abstract

An RFID tag'"'"'s mobility can be increased and cost can be decreased by using high-performance mobile power antennas instead of battery powered tags. Disclosed are some power antennas that include a half wave rectifier, a full wave rectifier, and a voltage multiplier. These antennas can be cascaded to boost the power or voltage gain. Additionally, planar elements can be added to increase efficiency without decreasing mobility.

Claims

1. In a radio frequency tag system for operating within a carrier frequency band above 900 megahertz containing a carrier frequency above 900 megahertz which produces an electromagnetic field, said radio frequency tag system comprising:

(a) a transmitter system for transmitting radio frequency electromagnetic energy in the carrier frequency band above 900 megahertz containing said carrier frequency above 900 megahertz so as to produce the electromagnetic field; and

(b) a radio frequency tag for receiving power from the electromagnetic field, said radio frequency tag comprising tag circuitry;

(c) said radio frequency tag comprising an antenna configuration that is substantially resonant at the carrier frequency band above 900 megahertz and is excited by the electromagnetic field to cause an induced current to be present at antenna terminals of the antenna configuration; and

(d) said antenna configuration developing sufficient power to operate said tag circuitry in the absence of transmitted electromagnetic energy for at least fifty microseconds.

2. In a radio frequency tag system according to claim 1, said antenna configuration being substantially resonant at carrier frequencies in a range of carrier frequencies between 902 megahertz and 928 megahertz.

3. In a radio frequency tag system according to claim 2, said antenna configuration supplying power to said tag circuitry via an impedance selected for substantially maximum power transfer to said tag circuitry.

4. In a radio frequency tag system according to claim 1, said antenna configuration supplying power to said tag circuitry via an impedance selected for substantially maximum power transfer to said tag circuitry.