Payment card signal characterization methods and circuits

• US 7,422,157 B2
• Filed: 07/15/2005
• Issued: 09/09/2008
• Est. Priority Date: 07/15/2004
• Status: Expired due to Fees

• 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
• Primary Examiner(s): St. Cyr; Daniel
• Application Number:
  US11/182,358
• Publication Number:
  US 20060022045A1
• Time in Patent Office: 1,152 Days
• Field of Search: 235/486, 235/380, 235/451, 235/487, 235/492
• US Class Current: 235/486
• 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 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;

(b) using a common mode rejection (CMR) circuit to demodulate the received load-modulated data signal and extract the load modulated subcarrier data signal;

(c) using the reference antenna to transmit power and data commands from a reference reader to the payment card on RF carrier signal, wherein 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, and wherein the average values refer to values representative of the behaviors of the several readers and interacting cards deployed in an electronic payment system.

2. The method for claim 1 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.

3. The method for claim 1 further comprising step (d) of using an analog-to-digital converter to sample the extracted signal.