TRANSPONDERS AND METHODS FOR OPERATING A TRANSPONDER

• US 20100073143A1
• Filed: 12/19/2007
• Published: 03/25/2010
• Est. Priority Date: 01/08/2007
• Status: Active Grant

• Current Assignee: Quotainne Enterprises LLC
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Schaffler, Gerald
• Granted Patent: US 8,836,481 B2
• Time in Patent Office: Days
• US Class Current: 340/10.400
• 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: G06K 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions

Abstract

In a method for operating a transponder (1, 41), the transponder (1, 4) receives a signal from a transmitter (2, 42). The signal comprises an information about a reference sensitivity and the transponder (1, 41) has an input sensitivity such that the transponder (1, 41) detects only signals above a certain power corresponding to the input sensitivity. In response to the received signal, the input sensitivity of the transponder (1, 41) is adjusted to the reference sensitivity.

Claims

1. A method for operating a transponder, comprising:

receiving a signal from a transmitter with a transponder having an input sensitivity such that said transponder detects only signals above a certain power corresponding to said input sensitivity;

said signal comprising an information about a reference sensitivity; and

adjusting said input sensitivity to said reference sensitivity.

2. The method of claim 1, wherein said information about said reference sensitivity comprises an information about a reference threshold voltage for an antenna of said transponder;

said antenna being designed to capture signals intended for said transponder and said transponder being designed to adjust said input sensitivity such that said transponder detects only signals causing a voltage across said antenna above said reference threshold voltage.

3. The method of claim 1, further comprising detecting an ambient attenuation of signals to be detected by said transponder;

and

adjusting said input sensitivity of said transponder so that said input sensitivity corresponds to said reference sensitivity without ambient attenuation.

4. A method for operating a transponder, comprising:

receiving a signal from a transmitter with a transponder having an input sensitivity such that said transponder detects only signals above a certain power corresponding to said input sensitivity;

said signal comprising an information about a distance within which said transponder shall be able to detect signals sent by said transmitter; and

adjusting said input sensitivity of said transponder so that said transponder detects only signals sent by said transmitter, if said transponder is within said distance to said transmitter.

5. The method of claim 4, further comprising detecting an ambient attenuation of signals to be detected by said transponder;

and

adjusting said input sensitivity of said transponder so that said attenuation is compensated.

6. A transponder comprising a receiver to receive signals sent by a transmitter;

said receiver having an input sensitivity such that said transponder detects only signals above a certain power corresponding to said input sensitivity and said transponder being configured to adjust said input sensitivity to a reference sensitivity in response to a received signal sent by said transmitter;

said received signal comprising an information about said reference sensitivity.

7. The transponder of claim 6, further comprising an antenna designed to capture signals intended for said transponder;

wherein said information about said reference sensitivity comprises an information about a reference threshold voltage so that said transponder adjusts said input sensitivity to detect only signals causing a voltage across said antenna above said reference threshold voltage.

8. The transponder of claim 6, further comprising a device for detecting an ambient attenuation of signals to be detected by said transponder;

said transponder being configured to adjust said input sensitivity so that said transponder has an input sensitivity corresponding to said reference sensitivity without attenuation.

9. A transponder comprising a receiver to receive signals sent by a transmitter;

said receiver having an input sensitivity such that said transponder detects only signals above a certain power corresponding to said input sensitivity and said transponder being configured to adjust said input sensitivity in response to a received signal sent by said transmitter and comprising an information about a distance so that said transponder detects only signals sent by said transmitter, if said transponder is within said distance to said transmitter.

10. The transponder of claim 9, further comprising a device for detecting an ambient attenuation of signals to be detected by said transponder;

said transponder being configured to adjust said input sensitivity so that said attenuation is compensable.