HIGH SPEED CONTACTLESS COMMUNICATION

• US 20100252631A1
• Filed: 04/01/2009
• Published: 10/07/2010
• Est. Priority Date: 04/01/2009
• Status: Abandoned Application

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Kargl, Walter
• Application Number:
  US12/416,441
• Publication Number:
  US 20100252631A1
• Time in Patent Office: Days
• US Class Current: 235/444
• 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: H03J 7/065 the counter or frequency divider being used in a phase locked loop
• CPC Class Codes: H04L 2027/0016 Stabilisation of local oscillators
• CPC Class Codes: H04L 27/02 Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation H04L27/32 takes precedence

Abstract

A contactless reader including a crystal oscillator configured to generate a first signal having a first frequency, a phase-locked loop configured to generate a crystal-accurate second frequency derived from the first frequency of the first signal, and a signal generator configured to generate a carrier signal having the crystal-accurate second frequency.

Claims

1. A contactless reader comprising:

a crystal oscillator configured to generate a first signal having a first frequency;

a phase-locked loop configured to generate a crystal-accurate second frequency derived from the first frequency of the first signal; and

a signal generator configured to generate a carrier signal having the crystal-accurate second frequency.

2. The contactless reader of claim 1, further comprising a modulator configured to modulate data onto the carrier signal.

3. The contactless reader of claim 1, wherein the second frequency is greater than the first frequency.

4. The contactless reader of claim 1, wherein the first frequency is in the High Frequency (HF) range.

5. The contactless reader of claim 1, further comprising a demodulator configured to demodulate data from a response signal transmitted by a contactless card.

6. The contactless reader of claim 1, wherein the second frequency is in the microwave frequency range.

7. The contactless reader of claim 1, wherein the first signal can be used to supply power to a contactless card.

8. The contactless reader of claim 2, wherein the modulator is further configured to modulate data onto the first signal prior to modulating data on the carrier signal.

9. A contactless card comprising:

an RF interface configured to receive a first signal having a first frequency;

a phase-locked loop configured to generate a second frequency derived from the first frequency; and

a signal generator configured to generate a response signal having the second frequency.

10. The contactless card of claim 9, further comprising a modulator configured to modulate data onto the response signal.

11. The contactless card of claim 9, wherein the first frequency and the second frequency are crystal-accurate.

12. The contactless card of claim 9, wherein the second frequency is in the microwave frequency range.

13. The contactless card of claim 9, wherein the RF interface is further configured to receive a carrier signal operating in the microwave frequency range.

14. The contactless communication system of claim 9, wherein the contactless card further comprises a rectifier configured to derive power from the first signal.

15. The contactless communication system of claim 9, wherein the contactless card further comprises a clock recovery unit coupled to the phase-locked loop, and configured to control timing of receipt and transmission of data.

16. A contactless communication system comprising:

a reader comprising;

an crystal oscillator configured to generate a first signal having a first frequency;

a first phase-locked loop configured to generate a crystal-accurate second frequency derived from the first frequency of the first signal;

a first signal generator configured to generate a carrier signal having the second frequency; and

a first modulator configured to modulate data onto the carrier signal; and

a contactless card comprising;

an antenna tuned to at least the first frequency;

a second phase-locked loop configured to derive the second frequency from the first frequency, wherein the second frequency is crystal-accurate; and

a second signal generator device configured to generate a response signal having the second frequency.

17. The contactless card of claim 16, further comprising a second modulator configured to modulate data onto the response signal.

18. The contactless communication system of claim 16, wherein the contactless card further comprises a second antenna tuned to the second frequency.

19. The contactless communication system of claim 16, wherein the second frequency is higher than the first frequency.

20. The contactless communication system of claim 16, wherein the second frequency enables the contactless reader and the contactless card to communicate at a data rate corresponding to a data rate of a USB standard.

21. The contactless communication system of claim 20, wherein the USB standard is selected from the group of USB standards consisting of USB 1.0, USB 1.1, and USB 2.0.

22. The contactless communication system of claim 16, wherein the modulator is further configured to modulate data on the first signal prior to modulating data on the carrier signal.

23. A contactless communication method comprising:

generating a first signal having a first frequency, by an crystal oscillator;

generating a carrier signal having a crystal-accurate second frequency derived from the first signal, by a phase-locked loop;

modulating data onto the carrier signal, by a modulator; and

transmitting the carrier signal to a contactless card, by an RF interface.

24. The contactless communication method of claim 23, further comprising modulating data on the first signal prior to the modulating data on the carrier signal.

25. A contactless communication method comprising:

receiving a first signal having a first frequency, by an RF interface;

generating a crystal-accurate second frequency derived from the first frequency, by a phase-locked loop;

generating a response signal having the second frequency, by a signal generator; and

transmitting the response signal to a reader by the RF interface.