Transmission error resistant reader station

• US 20050223280A1
• Filed: 04/23/2003
• Published: 10/06/2005
• Est. Priority Date: 05/15/2002
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Bergler, Heimo, Ully, Klaus, Meindl, Wolfgang
• Granted Patent: US 7,752,660 B2
• Time in Patent Office: Days
• US Class Current: 714/18
• 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: 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

Provided in a reception device (10) for receiving a transmission signal (US) in which, adhering to a communications protocol, reception data (ED) can be transmitted to the reception device (10) from a transmission device (2, 3) are reception means (12) for receiving the transmission signal (US), and evaluation means (16) for evaluating the received transmission signal (US) and for emitting a bit sequence (BFT) received in the transmission signal (US), which bit sequence (BFT) may contain bits of reception data (ED) transmitted from the transmission device (2, 3) but also bits (SB) occasioned by an interference to the transmission signal (US), and checking means (18) for checking whether the received bit sequence (BFT) infringes a rule of the communications protocol, wherein the reception device (10) is designed to continue with the reception of the transmission signal (US) and the checking of the received bit sequence (BFT) following the occurrence of an infringement of the communications protocol.

Claims

1. A reception device for receiving a transmission signal in which, adhering to a communications protocol, reception data can be transmitted to the reception device (10) from a transmission device, with reception means for receiving the transmission signal and with evaluation means for evaluating the received transmission signal and for emitting a bit sequence received in the transmission signal, which bit sequence may contain bits of reception data transmitted from the transmission device but also bits occasioned by an interference to the transmission signals, and with checking means for checking whether the received bit sequence infringes a rule of the communications protocol, characterized in that the reception device is designed to continue with the reception of the transmission signal and the checking of the received bit sequence following the occurrence of an infringement of the communications protocol.

2. A reception device as claimed in claim 1, characterized in that the checking means is designed such that, following the occurrence of an infringement of a rule of the communications protocol, it emits communication error information indicating the infringed rule.

3. A reception device as claimed in claim 1, characterized in that the checking means is designed to check whether the first bits of the received bit sequence have already been received before the expiry of a lead period, which starts from the start of a reception period, and therefore a first rule of the communications protocol has been infringed, wherein the reception device is designed, if this is the case, to reject the bits of the received bit sequence received before the expiry of lead period and to continue with the reception of the transmission signal and the checking of the bits of the received bit sequence received following expiry of the lead period.

4. A reception device as claimed in claim 1, characterized in that the checking means is designed to check the received bit sequence as to whether redundancy information contained at a predetermined bit position in valid reception data identifies defective bits in the received bit sequence, and therefore a second rule of the communications protocol has been infringed, wherein the reception device is designed, if this is the case, to reject the bits of the received bit sequence identified as defective, and to continue with the reception of the transmission signal and the checking of the subsequent bit sequence received.

5. A reception device as claimed in claim 1, characterized in that the checking means is designed to check the received bit sequence, as to whether a framebit sequence predetermined by the communications protocol is missing from a predetermined bit position in the received bit sequence, and therefore a third rule of the communications protocol has been infringed, wherein the reception device is designed, if this is the case, to reject the bit sequence already received, and to continue with the reception of the transmission signal and the checking of the subsequent bit sequence received.

6. A reception device as claimed in claim 2, characterized in that the checking means is designed to check whether, starting from the range of a reception period, a maximum reception period has already expired, wherein the checking means is designed, if this is the case, to emit exceeding-of-reception-period information or, if an infringement of the communications protocol has been detected during this reception period, is designed to emit communication error information.

7. A reception device as claimed in claim 1, characterized in that the reception device is provided in a base station and is designed for contactless communication with at least one transponder forming the transmission device.

8. A reception device as claimed in claim 2, characterized in that buffer storage means is provided for storing the received bit sequence emitted by the evaluation means, and for storing the detected communication error information.

9. A reception device as claimed in claim 6, characterized in that counter means are provided for determining the reception period that has already passed, and that this time measurement is interrupted by the counter means as soon as a further bit has been received in the transmission signal and that this time measurement is resumed by the counter means as soon as the infringement of a rule of the communications protocol has been established by the checking means.

10. A reception method for receiving a transmission signal in which, adhering to a communications protocol, reception data can be transmitted to the reception device from a transmission device wherein the following steps are followed:

reception of the transmission signal;

evaluation of the received transmission signal and emission of a bit sequence received in the transmission signal, which bit sequence may contain bits of reception data transmitted from the transmission device but also bits occasioned by an interference to the transmission signal;

checking whether the received bit sequence infringes a rule of the communications protocol;

characterized in that, following the occurrence of an infringement of the communications protocol, the reception of the transmission signals and the checking of the received bit sequence are continued.

11. A reception method as claimed in claim 10, characterized in that, in the case of the occurrence of an infringement of a rule of the communications protocol, communication error information indicating the infringed rule is emitted.

12. A reception method as claimed in claim 10, characterized in that the received bit sequence is checked as to whether the first bits of the received bit sequence have already been received before the expiry of a lead period, which starts from the start of a reception period, and therefore a first rule of the communications protocol has been infringed, whereupon, if this is the case, the bits of the received bit sequence received before the expiry of lead period are rejected, and the reception of the transmission signal and the checking of the bits of the received bit sequence received following expiry of the lead period are continued.

13. A reception method as claimed in claim 10, characterized in that the received bit sequence is checked as to whether redundancy information contained at a predetermined bit position in valid reception data identifies defective bits in the received bit sequence, and therefore a second rule of the communications protocol has been infringed, whereupon, if this is the case, the bits of the received bit sequence identified as defective are rejected, and the reception of the transmission signal and the checking of the subsequent bit sequence received are continued.

14. A reception method as claimed in claim 10, characterized in that the received bit sequence is checked as to whether a framebit sequence predetermined by the communications protocol is missing from a predetermined bit position in the received bit sequence, and therefore a third rule of the communications protocol has been infringed, whereupon, if this is the case, the bits identified as defective in the received bit sequence are rejected, and the reception of the transmission signal and the checking of the subsequent bit sequence received are continued.

15. A reception method as claimed in claim 11, characterized in that a check is made as to whether, starting from the start of a reception period, a maximum reception period has already expired, whereupon, if this is the case, exceeding-of-reception-period information is emitted or, if an infringement of the communications protocol has been detected during this reception period, communication error information is emitted.

16. A reception method as claimed in claim 15, characterized in that the reception period that has already passed is determined, and that this time the measurement is interrupted as soon as a further bit has been received in the transmission signal, and that this time measurement is continued as soon as the infringement of a rule of the communications protocol has been established.