Payment card signal characterization methods and circuits

• US 20060022045A1
• Filed: 07/15/2005
• Published: 02/02/2006
• Est. Priority Date: 07/15/2004
• Status: Active Grant

• Current Assignee: Mastercard International Incorporated (MasterCard Incorporated)
• Original Assignee: Mastercard International Incorporated (MasterCard Incorporated)
• Inventors: Smets, Patrick, Garrett, Duncan, Van De Velde, Eddy Lodewijk Hortensia
• Granted Patent: US 7,422,157 B2
• Time in Patent Office: Days
• US Class Current: 235/451
• CPC Class Codes: G01R 31/302 Contactless testing G01R31/66 takes precedence
• CPC Class Codes: G01R 31/308 using non-ionising electromagnetic radiation, e.g. optical radiation investigating or analysing materials by the use of optical means G01N21/00; image analysis G06T7/00
• CPC Class Codes: G06K 17/00 Methods or arrangements for effecting co-operative working between equipments covered by two or more of main groups G06K1/00 - G06K15/00, e.g. automatic card files incorporating conveying and reading operations
• CPC Class Codes: G06K 7/00 Methods or arrangements for sensing record carriers, e.g. for reading patterns methods or arrangements for marking the record carrier in digital fashion G06K1/00; pattern recognition G06F18/00; arrangements for image or video recognition or understanding G06V10/00; character recognition, recognising digital ink or document-oriented image-based pattern recognition G06V30/00
• 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 7/0095 Testing the sensing arrangement, e.g. testing if a magnetic card reader, bar code reader, RFID interrogator or smart card reader functions properly testing of electrical circuits G01R31/28
• CPC Class Codes: G06K 7/10019 resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. collision between the communication channels used by wireless communication devices, where the solution is not particularly adapted for RFIDs or the like, H04W74/08
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10465 the interrogation device being capable of self-diagnosis, e.g. in addition to or as part of the actual interrogation process testing of electrical circuits in general G01R31/28
• CPC Class Codes: G06Q 20/327 Short range or proximity payments by means of M-devices
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G07F 7/084 Additional components relating to data transfer and storing, e.g. error detection, self-diagnosis
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system

Abstract

A reference reader is provided for testing contactless electronic payment cards whose data transmissions are via weak load modulated RF carrier signals. The reference reader includes a reader antenna and a coupled common mode rejection circuit. The common mode rejection circuit is configured to demodulate carrier signals received at the reader antenna to retrieve payment card data signals having low modulation indices.

Claims

1. A reference reader for testing a payment card that can be used with any of several card readers deployed in an electronic payment system, the reference reader comprising:

an electronic circuit whose external behavior is representative of the behaviors of the several readers deployed in the electronic payment system, and wherein the electronic circuit is configured to exhibit the representative external behavior to the payment card under test; and

a CMR circuit for demodulating amplitude-modulated data signals received at the reader.

2. The reference card of claim 1 wherein the several readers are contactless payment card readers, wherein the reference reader electronic circuit comprises an antenna having a resonant frequency of about 13.56 MHz, and wherein an output lead of the an antenna is connected to the CMR circuit.

3. The reference reader of claim 1 wherein the antenna, electronic circuits and CMR circuit are fabricated on a printed circuit board.

4. The reference reader of claim 1 wherein the CMR. circuit comprises:

a phase locked loop (PLL) circuit;

a differentiator; and

an amplifier.

5. The reference reader of claim 1 wherein the CMR. circuit further comprises an analog-to-digital converter.

6. A reference reader for testing a payment card that can be used with any of several card readers deployed in an electronic payment system, the reference reader comprising:

an antenna tuned to an RF carrier frequency, wherein the payment card under test generates load-modulated data signals superimposed on a RF carrier signal received by the antenna; and

a coupled CMR circuit, which demodulates the load modulated card data signals received by the antenna.

7. The reference reader of claim 6 wherein the RF carrier signal is a 13.56 MHz carrier signal, and wherein the load-modulated card data signal is an 847.5 kHz sub-carrier.

8. The reference reader of claim 6 wherein the antenna and the CMR circuit are fabricated on a printed circuit board.

9. The reference reader of claim 6 wherein the CMR. circuit comprises:

a phase locked loop (PLL) circuit;

a differentiator; and

an amplifier.

10. The reference reader of claim 9 wherein the CMR. circuit further comprises an analog-to-digital converter.

11. A method for testing data transmission functions of contactless payment card that can be used with any of several card readers deployed in an electronic payment system, wherein the payment card transmits data by load modulating a subcarrier of an RF carrier signal, the method comprising the steps of:

(a) using a reference antenna tuned to the RF carrier signal frequency to receive a load-modulated data signal generated by the payment card; and

(b) using a CMR circuit to demodulate the received load-modulated data signal and extract the load modulated subcarrier data signal.

12. The method for claim 11 further comprising the step (c) of using a reference antenna to transmit power and data commands from the reference reader to the payment card on RF carrier signal.

13. The method for claim 12 wherein the step (c) comprises using the reference antenna to transmit power that has an average value and transmit data commands that are average value commands to the PICC, wherein the average values refer to values representative of the behaviors of the several readers and interacting cards deployed in an electronic payment system.

14. The method for claim 11 wherein step (b) of using a CMR circuit to demodulate the received load-modulated data signal and extract the load modulated subcarrier data signal comprises reducing the carrier signal amplitude to increase the modulation index of received signal.

15. The method for claim 11 further comprising step (d) of using an analog-to-digital converter to sample the extracted signal.