Communication between a transponder and an interrogator

• US 20040185806A1
• Filed: 05/10/2004
• Published: 09/23/2004
• Est. Priority Date: 05/03/2001
• Status: Abandoned Application

• Current Assignee: iPico Innovation Inc.
• Original Assignee: iPico Innovation Inc.
• Inventors: Van Zyl Smit, Hendrik
• Application Number:
  US10/476,838
• Publication Number:
  US 20040185806A1
• Time in Patent Office: Days
• US Class Current: 455/127.1
• 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

Abstract

A transponder (10) includes an activation circuit (12) responsive to an activation signal and having a power output, a coding circuit (14) connected to the power output of the activation circuit to produce a code modulated response signal on receipt of the activation signal, and a response circuit (16) connected to the coding circuit. The response circuit (16) is configured to transmit the code modulated response signal, and is a ringing circuit.

Claims

1. A transponder which includes

an activation circuit responsive to an activation signal and having a power output;

a coding circuit connected to the power output of the activation circuit to produce a code modulated response signal on receipt of the activation signal; and

a response circuit connected to the coding circuit and configured to transmit the code modulated response signal, the response circuit being a ringing circuit.

2. A transponder as claimed in claim 1, in which the activation circuit is responsive to an activation signal at a first frequency, and the response circuit is configured to transmit the code modulated response signal at a second, different frequency.

3. A transponder as claimed in claim 2, in which the second frequency is higher than the first frequency.

4. A transponder as claimed in any one of the preceding claims, in which the response circuit is a series coupled inductor/capacitor circuit.

5. A transponder as claimed in any one of claims 1 to 3 inclusive, in which the response circuit is a parallel coupled inductor/capacitor circuit.

6. A transponder as claimed in any one of the preceding claims, in which the coding circuit is configured to produce a response signal which is digitally switched.

7. A transponder as claimed in claims 6, in which the coding circuit is configured to produce a code modulated response signal which includes a plurality of pulses each time the coding circuit is switched to set the response circuit ringing.

8. A transponder as claimed in any one of the preceding claims, in which the response circuit is configured to produce a response signal of shorter duration than the activation signal, providing the response signal with a higher power output.

9. A transponder as claimed in any one of the preceding claims, in which the coding circuit is configured to produce the coded signal in a plurality of discrete bursts in response to a single activation signal.

18. A transponder as claimed in claim 1 or claim 10, substantially as herein described and illustrated.

10. A transponder which includes

an activation circuit responsive to an activation signal and having a power output;

a coding circuit connected to the power output of the activation circuit to produce a code modulated response signal on receipt of the activation signal; and

a response circuit connected to the coding circuit and configured to transmit the code modulated response signal, the response circuit being a switched oscillation circuit.

11. A transponder as claimed in claim 10, in which the switched oscillation circuit includes a transistor driven oscillator.

12. A method of transmitting a response signal from a transponder in response to an activation signal received from an interrogator, the method including

powering a coding circuit to produce a code modulated signal;

and

ringing a response circuit with the code modulated signal to transmit the coded signal to the interrogator.

13. A method as claimed in claim 12, in which the activation signal is at a first frequency and the transmitted response signal is at a second, different frequency.

14. A method as claimed in claim 13, in which the second frequency is higher than the first frequency.

15. A method as claimed in any one of claims 12 to 14 inclusive, in which the modulated signal is produced in bursts.

16. A method as claimed in any one of claims 12 to 15 inclusive, in which the coding circuit is digitally switched to produce the code modulated signal and in which the code modulated signal includes a plurality of pulses corresponding to each switching of the coding circuit.

19. A method of transmitting a response signal as claimed in claim 12 or claim 17, substantially as herein described and illustrated.

17. A method of transmitting a response signal from a transponder in response to an activation signal received from an interrogator, the method including

powering a coding circuit to produce a code modulated signal;

and

switching an oscillation circuit with the code modulated signal to transmit the coded signal to the interrogator.

20. A new transponder or a new transmission method, substantially as herein described.