Method and arrangement for encoding/decoding a signal at a first and second communication node in a road vehicle
Method for encoding/decoding a signal at a first and second communication node (N 1 ; N 2 ) in a road vehicle. A signal ( 1 ) from an on-board sensor ( 10 ) is encoded using a first encoding scheme (a), encoding the formed single encoded sensor signal ( 1 a ) using a second encoding scheme (b), decoding this double encoded sensor signal ( 1 ab ) in the second communication node (N 2 ) based on the second encoding scheme (b), forming a decoded single encoded sensor signal ( 1 a ′). In the first communication node (N 2 ), performing a comparison analysis, comprising at least one of the following: comparing the decoded single encoded sensor signal ( 1 a ′) with a stored single encoded sensor signal ( 1 a ), or after encoding the decoded single encoded sensor signal ( 1 a ′) with the second encoding scheme (b) comparing ( 110 ) the thus formed double encoded sensor signal ( 1 a′b ) with a stored double encoded sensor signal ( 1 ab ). If the compared sensor signals ( 1 a ′,1 a; 1 ab, 1 a′b ) match, then sending ( 111 ) a signal to the second communication node (N 2 ) validating the sensor signal ( 1 ), and if they do not match, then initiating ( 112 ) a corrective action.
1. Method for encoding/decoding a signal at a first and second communication node in a road vehicle, the method comprising:
by means of an on-board sensor on said road vehicle, detecting environmental information associated with said road vehicle, in said first communication node:
encoding a signal representing said detected environmental information associated with said road vehicle using a first encoding scheme,
encoding a thus formed single encoded sensor signal using a second encoding scheme,
sending a thus formed double encoded sensor signal to said second communication node,
storing at least one of said single encoded sensor signal and said double encoded sensor signal in said first communication node,
in said second communication node:
decoding said double encoded sensor signal received from said first communication node based on said second encoding scheme, forming a decoded single encoded sensor signal,
sending said decoded single encoded sensor signal to said first communication node, and
in said first communication node:
performing a comparison analysis, comprising at least one of the following:
comparing said decoded single encoded sensor signal received from said second communication node with a stored single encoded sensor signal, or after encoding said decoded single encoded sensor signal received from said second communication node with said second encoding scheme, comparing said thus formed double encoded sensor signal with a stored double encoded sensor signal, wherein said compared sensor signals match, then sending a signal to the second communication node validating said sensor signal, if said compared sensor signals do not match, then initiating a corrective action.
2. The method of claim 1 , wherein said comparison analysis comprises comparing said decoded single encoded sensor signal with a stored single encoded sensor signal.
3. The method of claim 1 , wherein said comparison analysis comprises after encoding said decoded single encoded sensor signal received from said second communication node with said second encoding scheme, comparing said thus formed double encoded sensor signal with a stored double encoded sensor signal.
4. The method of claim 1 , wherein said first encoding scheme is a sensor identification code.
5. The method of claim 1 , wherein said second encoding scheme is an encryption based on a vehicle identification number of said road vehicle.
6. The method of claim 5 , wherein an encryption key used in said encryption is based on one or more of: date of manufacture of said on-board sensor, date of installation of said on-board sensor in said road vehicle, location of manufacturing of said on-board sensor, location of installation of said on-board sensor in said road vehicle, an on-board sensor manufacturing property, and an on-board sensor installation property.
7. The method of claim 5 , wherein said encryption is performed using an advanced encryption standard method.
8. The method of claim 5 , wherein said encryption includes a dynamically changing encryption key.
9. The method of claim 1 , wherein said corrective action comprises resending said double encoded sensor signal from said first communication node to said second communication node.
10. The method of claim 1 , wherein said corrective action comprises shutting down said on-board sensor.
11. The method of claim 1 , wherein said corrective action comprises shutting down said road vehicle.
12. The method of claim 1 , wherein upon receiving said validating signal from said first communication node in said second communication node, decoding a decoded single encoded sensor signal stored in said second communication node based on said first encoding scheme, and initiating an action based on a thus formed double decoded sensor signal.
13. Arrangement for encoding/decoding a signal at a first and second communication node in a road vehicle, wherein said arrangement comprises:
a first communication node and a second communication node,
at least one on-board sensor on said road vehicle, arranged to detect environmental information associated with said road vehicle, wherein said first communication node is arranged to:
in a first encoding unit, encode a signal representing said detected environmental information associated with said road vehicle using a first encoding scheme, and further encode said formed single encoded sensor signal using a second encoding scheme, and send a thus formed double encoded sensor signal to said second communication node, and
in a storing unit store at least one of said single encoded sensor signal and said double encoded sensor signal, wherein said second communication node is arranged to in a decoding unit decode said double encoded sensor signal received from said first communication node based on said second encoding scheme, forming a decoded single encoded sensor signal, and send said decoded single encoded sensor signal said first communication node, wherein said first communication node further is arranged to in an analysis unit perform a comparison analysis comprising at least one of the following actions:
compare said decoded single encoded sensor signal received from said second communication node with a single encoded sensor signal stored in said storing unit, or compare, subsequent to encoding said decoded single encoded sensor signal received from said second communication node with said second encoding scheme in a second encoding unit, a thus formed double encoded sensor signal with a double encoded sensor signal stored in said storing unit, wherein if said compared sensor signals match, then send a signal to said second communication node validating said sensor signal, if said compared sensor signals do not match, then initiate a corrective action.
14. The arrangement of claim 13 , wherein said first and second encoding units is the same encoding unit.
15. A road vehicle comprising said arrangement for encoding/decoding a signal at a first and second communication node according to claim 13 .