Reliable Data Transmission with Reduced Bit Error Rate

• US 20150026547A1
• Filed: 10/06/2014
• Published: 01/22/2015
• Est. Priority Date: 03/04/2011
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Hammerschmidt, Dirk, Dittfeld, Timo, Brewerton, Simon
• Granted Patent: US 9,361,179 B2
• Time in Patent Office: Days
• US Class Current: 714/807
• CPC Class Codes: B60R 2021/01286 Electronic control units
• CPC Class Codes: B60R 21/01 Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents electrical circuits for transmission of signals between steering wheel and the vehicle itself B60R16/027; for electrically actuating belt retractor locking means B60R22/343
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00
• CPC Class Codes: H03M 13/093 CRC update after modification of the information word
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 2001/0094 Bus

Abstract

A data transmission system includes at least one transmission line. A sender is configured to send data frames to the at least one transmission line and a recipient is configured to receive the data frames from the at least one transmission line. The sender and the recipient are both configured to determine a check sum based on a plurality of corresponding data frames that are sent to and, respectively, received from the at least one transmission line. A check sum comparing unit is configured to receive and to compare the check sum determined by the sender and the corresponding check sum determined by the recipient. The check sum comparing unit is also configured to signal a transmission error or initiate a safety function when the check sums compared are not equal.

Claims

1. A system comprising:

a recipient configured to receive data frames from at least one transmission line, wherein the recipient is configured to determine a recipient check sum based on a plurality of corresponding data frames that are received from the at least one transmission line;

a check sum comparing unit configured to receive and to compare the recipient check sum with a corresponding sender check sum determined by a sender transmitting the data frames received at the recipient and;

a switch coupled to an output of the recipient and coupled to be activated upon receipt of a signal; and

a safety circuit coupled to the check sum comparing unit, wherein the safety circuit is configured to transmit a deactivation signal configured to prevent the switch from conducting a ON current if the check sums compared are not equal.

2. The system of claim 1, wherein the safety circuit is configured to transmit the deactivation signal at the same time the recipient sends the signal for activating the switch.

3. The system of claim 1, wherein the check sum comparing unit is included in the sender, the recipient, or in a transmission line monitoring unit arranged separately from the sender and the recipient.

4. The system of claim 1, further comprising:

a SPI master unit comprising the recipient, wherein the switch is configured to be coupled to a squib upon activation, and wherein the SPI master unit, the switch, and the safety circuit are part of an electronic control unit system for air bag deployment.

5. The system of claim 1, wherein the recipient comprises a recipient check sum calculation unit configured to calculate the recipient check sum based on the data frames received from the at least one transmission line, wherein the calculated recipient check sum is continuously updated each time a data frame is received, and wherein the calculated recipient check sum depends on all data frames that have been received after a reset of the recipient check sum calculation unit, and

wherein the check sum comparing unit is further configured to signal a transmission error or initiate a safety function when a sender check sum determined by the sender is not equal to the recipient check sum.

6. The system of claim 1, wherein the sender check sum is a polynomial code check sum generated by a cyclic redundancy check (CRC).

7. The system of claim 6, wherein each individual data frame includes a further check sum depending only on information included in the respective data frame.

8. The system of claim 7, wherein the further check sum is a polynomial code check sum generated by a cyclic redundancy check, wherein the order of the further check sum is lower than the order of the check sums which are based on a plurality of corresponding data frames.

9. A system comprising:

a sender configured to send data frames on at least one transmission line to a recipient, wherein the sender is configured to determine a sender check sum based on a plurality of corresponding data frames that are sent from the at least one transmission line;

a check sum comparing unit configured to receive and to compare the sender check sum and a corresponding recipient check sum determined by the recipient;

a switch coupled to an output of the recipient and coupled to be activated upon receipt of a signal; and

a safety circuit coupled to the check sum comparing unit, wherein the safety circuit is configured to transmit a deactivation signal configured to prevent the switch from conducting a ON current if the check sums compared are not equal.

10. The system of claim 9, wherein the sender is configured to send the determined check sum only when the sender receives the signal for activating the switch to be transmitted to the receiver.

11. The system of claim 9, wherein the check sum comparing unit is included in the sender, the recipient, or in a transmission line monitoring unit arranged separately from the sender and the recipient.

12. The system of claim 9, further comprising:

a serial peripheral interface (SPI) slave unit comprising the sender, wherein the SPI slave unit is configured to be coupled to a plurality of external sensors, wherein the SPI slave unit, the switch, and the safety circuit are part of an electronic control unit system for air bag deployment.

13. The system of claim 9,

wherein the sender comprises a sender check sum calculation unit configured to calculate the sender check sum based on the data frames sent to the at least one transmission line, wherein the calculated sender check sum is continuously updated each time a data frame is sent to the at least one transmission line, and wherein the calculated sender check sum depends on all data frames that have been sent to the at least one transmission line after a reset of the sender check sum calculation unit,

wherein the check sum comparing unit is further configured to signal a transmission error or initiate a safety function when the sender check sum is not equal to the recipient check sum.

14. The system of claim 9, wherein the sender check sum is a polynomial code check sum generated by a cyclic redundancy check (CRC).

15. The system of claim 14, wherein each individual data frame includes a further check sum depending only on information included in the respective data frame.

16. The system of claim 15, wherein the further check sum is a polynomial code check sum generated by a cyclic redundancy check, wherein the order of the further check sum is lower than the order of the check sums which are based on a plurality of corresponding data frames.

17. A method for transmitting data frames from a sender to a recipient over a transmission channel, the method comprising:

providing a sender check sum based on a plurality of data frames sent over the transmission channel to the recipient;

providing a recipient check sum based on a plurality of data frames received at the recipient;

comparing the sender check sum with the corresponding recipient check sum; and

transmitting a deactivation signal configured to prevent a switch, coupled to an output of the recipient and configured to be activated upon receipt of a signal, from conducting a ON current if the sender check sum is not equal to the recipient check sum.

18. The method of claim 17, further comprising enabling the activation of the switch upon receipt of the signal if the sender check sum is equal to the recipient check sum.

19. The method of claim 17, further comprising receiving a signal indicating the firing of external sensors, and if the sender check sum is equal to the recipient check sum, activating the switch configured to activate a squib.

20. The method of claim 17, further comprising resetting the check sum determination, wherein the recipient check sums depend on all data frames which have been received after a reset.

21. The method of claim 17, further comprising resetting the sender check sum determination, wherein the sender check sums depend on all data frames which have been sent after a reset.

22. The method of claim 17, wherein providing the sender check sum comprises receiving the sender check sum at the recipient.

23. The method of claim 17, wherein providing the sender check sum comprises calculating the sender check sum based on the data frames sent through the transmission channel, wherein the calculated sender check sum is continuously updated each time a data frame is sent, and wherein the calculated sender check sum depends on all data frames that have been sent after a reset of a sender check sum calculation unit configured to calculate the sender check sum.

24. The method of claim 17, wherein providing the recipient check sum comprises receiving the recipient check sum at the sender.

25. The method of claim 17, wherein providing the recipient check sum comprises calculating the recipient check sum based on the data frames received from the transmission channel, wherein the calculated recipient check sum is continuously updated each time a data frame is received, and wherein the calculated recipient check sum depends on all data frames that have been received after a reset of a recipient check sum calculation unit configured to calculate the recipient check sum.