Wireless communications devices, methods of processing a wireless communication signal, wireless communication synchronization methods and a radio frequency identification device communication method

• US 20040067764A1
• Filed: 10/02/2002
• Published: 04/08/2004
• Est. Priority Date: 10/02/2002
• Status: Active Grant

• Current Assignee: Battelle Memorial Institute
• Original Assignee: Battelle Memorial Institute
• Inventors: Pratt, Richard M., Thompson, Steven B.
• Granted Patent: US 7,760,835 B2
• Time in Patent Office: Days
• US Class Current: 455/502
• 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 19/07758 arrangements for adhering the record carrier to further objects or living beings, functioning as an identification tag
• 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: H03K 5/135 by the use of time reference signals, e.g. clock signals
• CPC Class Codes: H03K 5/1565 the output pulses having a constant duty cycle
• CPC Class Codes: H04L 7/0066 detection of error based on transmission code rule
• CPC Class Codes: H04L 7/027 extracting the synchronising or clock signal from the received signal spectrum, e.g. by using a resonant or bandpass circuit

Abstract

Wireless communications devices, methods of processing a wireless communication signal, wireless communication synchronization methods and a radio frequency identification device communication method are described. In one aspect, a wireless communication device includes an antenna configured to receive electromagnetic energy corresponding to a wireless communication signal outputted using an interrogator and to output electrical energy corresponding to the received electromagnetic energy, communication circuitry coupled with the antenna and configured to sample the electrical energy to process the wireless communication signal, synchronization circuitry coupled with the antenna and the communication circuitry and configured to generate a clock signal to control sampling of the electrical energy using the communication circuitry, wherein the synchronization circuitry is configured to generate a plurality of transitions within the clock signal responsive to a plurality of transitions of the electrical energy during a first data period and wherein the synchronization circuitry is configured to generate a plurality of transitions within the clock signal during a second data period including generating at least one of the transitions independent of transitions of the electrical energy.

Claims

1. A wireless communication device comprising:

an antenna configured to receive electromagnetic energy corresponding to a wireless communication signal outputted using an interrogator and to output electrical energy corresponding to the received electromagnetic energy;

communication circuitry coupled with the antenna and configured to sample the electrical energy to process the wireless communication signal;

synchronization circuitry coupled with the antenna and the communication circuitry and configured to generate a clock signal to control sampling of the electrical energy using the communication circuitry;

wherein the synchronization circuitry is configured to generate a plurality of transitions within the clock signal responsive to a plurality of transitions of the electrical energy during a first data period; and

wherein the synchronization circuitry is configured to generate a plurality of transitions within the clock signal during a second data period including generating at least one of the transitions independent of transitions of the electrical energy.

2. The device of claim 1 wherein the synchronization circuitry is configured to generate the clock signal responsive to transitions of the electrical energy having a frequency less than a time constant of the synchronization circuitry and responsive to the time constant when a frequency of the transitions is greater than the time constant.

3. The device of claim 1 wherein the wireless communication signal comprises digital data encoded according to a biphase format.

4. The device of claim 1 wherein the wireless communication signal comprises digital data encoded according to a biphase mark format.

5. The device of claim 1 wherein the wireless communication signal comprises digital data encoded according to a biphase space format.

6. The device of claim 1 wherein the synchronization circuitry is implemented within an application specific integrated circuit.

7. The device of claim 1 wherein the communication circuitry is configured to implement radio frequency identification device communications.

8. The device of claim 1 wherein the communication circuitry is configured to implement backscatter modulation communications.

9. The device of claim 1 wherein the synchronization circuit is configured to generate the clock signal to control sampling of the communication circuitry during a plurality of different states of the electrical energy during the first data period and to control sampling a plurality of times during a same state of the electrical energy during the second data period.

10. A wireless communication device comprising:

an antenna configured to receive a wireless communication signal comprising encoded data in a biphase format having one transition for a first digital value and a plurality of transitions for a second digital value;

communication circuitry configured to sample the encoded data;

an edge detector configured to generate a plurality of pulses responsive to the transitions of the encoded data; and

an oscillator coupled with the edge detector and configured to output a signal responsive to the pulses to control sampling of the encoded data using the communication circuitry.

11. The device of claim 10 wherein the wireless communication signal comprises digital data encoded according to one of a biphase mark format and a biphase space format.

12. The device of claim 10 further comprising electrically isolating the edge detector and the oscillator during an absence of transitions.

13. The device of claim 10 wherein the oscillator is configured to oscillate at a frequency substantially twice a data rate of the encoded data.

14. The device of claim 10 wherein the oscillator is configured to oscillate at a frequency corresponding to a data rate of the encoded data.

15. The device of claim 10 wherein the synchronization circuitry comprises a flip-flop configured to provide a clock signal, and an inverter configured to invert the signal outputted from the oscillator and to apply the inverted signal to a clear input of the flip-flop to provide the clock signal having a plurality of rising edges at respective beginnings of data periods of the encoded data.

16. The device of claim 10 further comprising synchronization circuitry including the edge detector and the oscillator, and wherein the. synchronization circuitry is configured to provide a clock signal to be applied to the communication circuitry and to output the clock signal having a predefined value during an absence of encoded data.

17. The device of claim 10 wherein the communication circuitry is configured to implement backscatter modulation communications.

18. The device of claim 10 wherein the communication circuitry is configured to implement radio frequency identification device communications.

19. A method of processing a wireless communication signal comprising:

providing a radio frequency identification device;

receiving a data signal including a plurality of digital values within the radio frequency identification device;

sampling the data signal at a plurality of moments in time during individual ones of the digital values using the radio frequency identification device; and

wherein the sampling at one moment in time comprises sampling responsive to a transition in the data signal and the sampling at another -moment in time comprises sampling after the elapse of a predetermined period of-time without a transition in the data signal.

20. The method of claim 19 wherein the receiving the data signal comprises receiving the data signal comprising digital data encoded according to one of a biphase mark format and a biphase space format.

21. The method of claim 19 wherein the sampling at the one moment in time includes sampling responsive to the transition in the data signal occurring prior to the elapse of the period of time dictated by a time constant.

22. The method of claim 19 wherein the sampling at the another moment in time comprises sampling after the elapse of the period of time corresponding to a time constant.

23. The method of claim 19 wherein the sampling comprises sampling responsive to a clock signal, and further comprising providing the clock signal comprising a predefined digital value in the absence of encoded data within the data signal.

24. The method of claim 19 wherein the sampling comprises sampling at the one moment in time during plural different states of the data signal and corresponding to one of the digital values of the data signal and sampling at the another moment in time during a same state of the data signal during another of the digital values.

25. A wireless communication synchronization method comprising:

receiving a data signal;

generating a plurality of edge pulses corresponding to the data signal;

generating a plurality of transitions within a clock signal responsive to a plurality of edge pulses during a first digital value of the data signal;

generating a plurality of transitions within the clock signal during a second digital value of the data signal including generating at least one of the transitions independent of the edge pulses during the second digital value of the data signal; and

sampling the data signal using the clock signal.

26. The method of claim 25 wherein the receiving the data signal comprises receiving the data signal encoded with digital data according to one of a biphase mark and a biphase space format.

27. The method of claim 25 further comprising outputting the clock signal to communication circuitry using an oscillator having a oscillation frequency greater than a data rate of the data signal.

28. The method of claim 25 further comprising outputting the clock signal to communication circuitry using a flip-flop.

29. The method of claim 28 wherein the generating transitions during the second digital value comprises selectively clearing the flip-flop using an oscillator having an oscillation frequency substantially equal to a data rate of the data signal.

30. The method of claim 29 wherein the generating transitions during the first digital value comprises toggling the flip-flop at an increased frequency compared with the during the oscillation frequency.

31. The method of claim 25 further comprising outputting the clock signal having a predefined digital value during an absence of the data signal including digital data.

32. The method of claim 25 wherein the sampling comprises sampling the data signal a plurality of times during a data period of the data signal.

33. The method of claim 25 wherein the receiving the data signal comprises receiving the data signal within a radio frequency identification device.

34. The method of claim 25 further comprising providing the clock signal configured to control the sampling during a plurality of different states of the data signal during one digital value and a plurality of times during a same state of the data signal during another digital value.

35. A radio frequency identification device communication method comprising:

providing a radio frequency identification device including an oscillator;

receiving a data signal having a plurality of transitions within the radio frequency identification device, and wherein the data signal includes digital data encoded according to a data encoding format including one of a biphase mark format and a biphase space format;

generating a plurality of edge pulses corresponding to the transitions of the data signal;

generating a clock signal having a plurality of transitions using the oscillator;

generating the transitions of the clock signal using the edge pulses during a first digital value of the data signal;

generating at least one of the transitions of the clock signal using a time constant of the oscillator and independent of the edge pulses during a second digital value of the data signal;

sampling the data signal using the clock signal; and

backscatter modulating a continuous wave signal after the sampling to formulate a reply communication to the received data signal.