Method for data communication between a base station and a transponder

• US 20070063819A1
• Filed: 09/25/2006
• Published: 03/22/2007
• Est. Priority Date: 03/25/2004
• Status: Active Grant

• Current Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Original Assignee: Atmel Germany GmbH (Microchip Technology Incorporated)
• Inventors: Friedrich, Ulrich
• Granted Patent: US 8,761,149 B2
• Time in Patent Office: Days
• US Class Current: 340/10.100
• 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 7/10019 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 7/10297 arrangements for handling protocols designed for non-contact record carriers such as RFIDs NFCs, e.g. ISO/IEC 14443 and 18092 cryptographic protocols H04L9/00; network security protocols H04L63/00; real-time communication protocols in data switching networks H04L65/00; network protocols for data switching network services H04L67/00

Abstract

A method for data communication between a base station and at least one transponder by a high-frequency electromagnetic carrier signal is disclosed, onto which information packets are modulated, whereby each information packet has a header section, a middle section, and an end section and whereby the middle section has a data field for the transmission of data and/or address information and a protection field placed thereafter for the correction of errors in the transmission of the data and/or address information, whereby after the data field the base station inserts at least one control field, by which the protection field following the inserted control field can be changed in such a way that the duration of an information packet is set variably. The invention relates further to a base station for carrying out this method, to a data communication system containing a base station and at least one transponder in communicative wireless contact with the base station.

Claims

1. A method for data communication between a base station and at least one transponder by a high-frequency electromagnetic carrier signal, onto which information packets are modulated, wherein each information packet has a header section, a middle section, and an end section, and wherein the middle section has a data field for the transmission of data and/or address information and a protection field provided thereafter for the correction of errors in the transmission of the data and/or address information, the method comprising:

inserting by the base station, after the data field, at least one control field;

determining, based on data of the control field, at which point the protection field following a data field is canceled; and

variable adjusting, based on the data of the control field, a length of a transmitted information packet.

2. The method according to claim 1, wherein the control field is inserted immediately after the data field.

3. The method according to claim 1, wherein the control field is inserted after the data field and within the protection field.

4. The method according to claim 1, wherein the control field is inserted into the forward link of a data communication.

5. The method according to claim 1, wherein the base station sets a content of the control field depending on the transmitted data in the data field, and wherein the content of the control field predefines the place in the protection field where the control field is inserted.

6. The method according to claim 1, wherein the base station transmits at least one protection symbol in an area of the protection field in response to a response signal of the transponder, wherein the specific protection symbol is assigned a first value, which indicates to the transponder that the transmission of the specific data has occurred properly, and wherein the protection symbol is assigned at least one second value, which indicates to the transponder that the transmission of the specific data was faulty.

7. The method according to claim 6, wherein the data communication in the region of the protection field is continued if the control field has the first value.

8. The method according to claim 6, wherein the data communication is aborted in the area of the protection field and/or restarted from the start of the information packet, if the control field has the second value.

9. The method according to claim 6, wherein the protection symbol is assigned a third value, which indicates to the transponder that subsequent symbols of the protection field are to be skipped and/or further checking of the transmitted data is to be ended.

10. The method according to claim 1, wherein that the number of transmitted symbols in the middle section is controlled via the control field so that depending on the content of the control field a variable duration of a data transmission of an information packet is set.

11. The method according to claim 1, wherein a transponder, whose protocol does not support the function of the control field and thereby does not recognize its content, ignores the content of the control field.

12. The method according to claim 1, wherein that a transponder, whose protocol does not support the function of the control field and thereby does not recognize its content, no longer participates in further data communication with the base station.

13. The method according to claim 1, wherein at the beginning of the data communication transmission is performed in half-duplex operation, in which the base station transmits first at least one complete information packet in a forward link to the transponder and the transponder after this transmission transmits response signals back to the base station in a return link.

14. The method according to claim 13, wherein, after the transmission of at least one complete information packet in half-duplex operation, the data communication is continued in full-duplex operation, in which the transponder transmits back in each case, for a symbol transmitted by the base station in the forward link, a corresponding response signal using the backscatter technique.

15. The method according to claim 1, wherein the header section has control information for controlling the data communication, and wherein at least the number of data to be transmitted and their identification are defined by means of the control information.

16. The method according to claim 1, wherein the symbols in the protection field are configured as CRC protection symbols and/or parity bits, by which proper data communication of the information in the data field is assured.

17. The method according to claim 1, wherein that the data field contains commands, parameter data, address data, and/or program data.

18. The method according to claim 1, wherein the header section contains control symbols to control the data transmission of an information packet to be transmitted in each case.

19. The method according to claim 18, wherein the control symbols have a bit position indicator for the start of the middle section, the data field, the protection field, the control field, and/or the end section of the specific information packet.

21. A RFID data communication system comprising a base station according to claim 20, and at least one transponder, which wirelessly communicates with the base station by the method according to claim 1, wherein the transponder is a passive transponder, and wherein the transponder is operated in full-duplex with the base station in the return link.

22. The data communication system according to claim 21, wherein the transponder is configured to send return signals to the base station in response to signals transmitted from the base station.

23. The data communication system according to claim 21, wherein the transponder is a remote-controllable sensor, a temperature sensor, and/or a pressure sensor.

20. A base station for data communication with at least one transponder, the base station comprising:

a transmitting/receiving device for transmitting high-frequency carrier signals and for receiving corresponding response signals from the transponder;

an evaluation device operatively coupled to the transmitting/receiving device for comparing and evaluating the transmitted and the correspondingly associated response signals transmitted back by the transponder; and

a control device which is operatively coupled to the evaluation device and controls further data communication with at least one transponder depending on the evaluation in the evaluation device by inserting at least one control field in the forward link of a transmitted information packet.