Apparatus, method, and computer program product for establishing a remote data link with a vehicle with minimal data transmission delay

• US 6,604,038 B1
• Filed: 11/09/1999
• Issued: 08/05/2003
• Est. Priority Date: 11/09/1999
• Status: Expired due to Term

• Current Assignee: Power Talk Incorporated
• Original Assignee: Power Talk Incorporated
• Inventors: Lesesky, Alan C., Weant, Bobby Ray
• Primary Examiner(s): Nguyen, Tan Q.
• Assistant Examiner(s): Tran, Dalena
• Application Number:
  US09/435,931
• Time in Patent Office: 1,365 Days
• Field of Search: 701/49, 701/34, 340/988, 710/100, 710/105, 327/153, 713/400, 713/401, 370/452, 370/476, 370/451, 370/475
• US Class Current: 701/49
• CPC Class Codes: G07C 5/008 communicating information to a remotely located station transmission systems for measured values G08C
• CPC Class Codes: G07C 5/085 using electronic data carriers
• CPC Class Codes: G08G 1/20 Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 2012/40267 Bus for use in transportation systems

Abstract

The present invention provides several apparatus, methods, and computer program products for establishing a data communication link between an interrogation device and the data bus of a vehicle. Specifically, in one embodiment, the present invention provides apparatus, methods, and computer program products that process data transmitted to and from the data bus of a vehicle one bit at a time with minimal delay. The apparatus, methods, and computer program products of this embodiment also prevent propagation of false data to both the data bus and the interrogation device, which is generated by the transmission of data to and from the data bus. The present invention also provides apparatus and methods that reduce the introduction of false data in the form of signal noise onto the data bus of a vehicle when the data bus is not transmitting data to or receiving data from a remote location. In this embodiment, the present invention includes a switch, that in the open position isolates the data bus from a transceiver used to receive external data. The present invention also provides apparatus and methods that establish data communication links between interrogation devices and the data bus of a vehicle by transmitting a data link command alerting the data bus that the interrogation device is attempting to form a data communication link. In some embodiments, both the vehicle and remote interrogation device transmit a heartbeat signal to each other over a data communication link to signify that a data communication link is present. When the heartbeats signal is not received, the vehicle and interrogation device determine that the data link has ended.

Claims

1. An apparatus for establishing a data communication link between a data bus of a vehicle and a remote interrogation device where unwanted signals may be received by the data bus and corrupt data on the data bus, wherein said apparatus comprises:

a local transceiver in operable electrical communication with the data bus for transmitting data to and data from the data bus;

a local processor in operable electrical communication with both said transceiver and the data bus; and

a switch in operable electrical communication with said local processor, local transceiver, and the data bus, wherein said switch in a closed position connects said local transceiver and the data bus and in an open position isolates said local transceiver from the data bus, and wherein said local processor in a data transfer mode closes said switch and in an idle mode opens said switch such that in the idle mode unwanted signals received by said local transceiver are not input to the data bus.

2. An apparatus according to claim 1 further comprising a remote interrogation device having a transceiver in electrical communication with a remote processor for transmitting data to and receiving data from the data bus of the vehicle.

3. An apparatus according to claim 2, wherein in a data transfer mode, said remote processor of said interrogation device controls said remote transceiver to transmit a data link command to said local processor, and wherein upon receipt of the data link command, said local processor closes said switch to thereby establish a data link between the data bus and said remote processor.

4. An apparatus according to claim 3, wherein in a data transfer mode, said remote processor of said interrogation device controls said remote transceiver to sequentially transmit a plurality of data link commands to said local processor, wherein said apparatus further comprises a counter in electrical communication with said local processor, wherein said counter counts the number of times the data link command is received by said local processor, and wherein said local processor closes said switch when the number of times the data link command was received exceeds a predetermined threshold value to thereby create a data link between said remote processor and the data bus of the vehicle.

5. An apparatus according to claim 4, wherein said interrogation device controls said remote transceiver to sequentially transmit a data link command at a predetermined time intervals to said local processor, wherein said counter counts the number of times the data link command is received by said local processor, wherein said local processor monitors the time interval between receipt of each data link command, and wherein said local processor resets said counter if the data link command is not received within the predetermined time interval, such that the counter totals the number of times the data link command was transmitted consecutively.

6. An apparatus according to claim 3, wherein when transmitting data to the data bus in a data transfer mode, said remote processor periodically transmits a heartbeat signal indicating an established data link between said remote processor and the data bus, and wherein said local processor monitors an interval between receipt of the periodic heartbeat signal, and if the heartbeat signal is not received within a predetermined time interval, said local processor determines that that the data link is no longer viable and opens the switch thereby isolating the data bus from said local transceiver to alleviate the introduction of noise into the data bus.

7. An apparatus according to claim 3, wherein when data is transmitted to the data bus in a data transfer mode, said local processor monitors the data for errors and determines that that the data link is no longer viable when a predetermined percentage of the data received is in error, and wherein said local processor opens the switch thereby isolating the data bus from the local transceiver to alleviate the introduction of noise onto the data bus.

8. An apparatus according to claim 3, wherein when in the data transfer mode, said local processor periodically transmits a heartbeat signal indicating an established data link between said remote processor and the data bus, and wherein said remote processor monitors an interval between receipt of the periodic heartbeat signal, and if the heartbeat signal is not received within a predetermined time interval, said remote processor determines that that the data link is no longer viable and ceases transmitting data to said local transceiver.

9. A method for establishing a data communication link between a data bus of a vehicle having a transceiver for receiving data and a remote interrogation device where unwanted signals may be received by the data bus and corrupt data on the data bus, wherein said method comprises the steps of:

connecting the local transceiver and the data bus in a data transfer mode such that the data bus may receive data transmitted by the remote interrogation device;

in the data transfer mode, sequentially transmitting a plurality of data link commands to the data bus of the vehicle, wherein said connecting step comprises the steps of;

receiving the data link commands;

counting the number of times the data link command is received;

comparing the number of times the data link command is received to a predetermined threshold; and

connecting the data bus to the local transceiver when the number of times the data link command has been received exceeds the predetermined threshold; and

isolating the local transceiver from the data bus in an idle mode such that unwanted signals received by the transceiver are not input to the data bus.

10. A method according to claim 9, wherein in the data transfer mode said transmitting step comprises sequentially transmitting a data link command at a predetermined time interval to the data bus, wherein said counting step comprises counting the number of times the data link command is received, wherein said method further comprises the step of monitoring the time interval between receipt of each data link command and resetting said counting step if the data link command is not received within the predetermined time interval, such that said counting step totals the number of times the data link command was transmitted without interruption.

11. A method according to claim 9, wherein in the data transfer mode after said connecting step said method further comprises the steps of:

periodically transmitting a heartbeat signal from the remote processor to the data bus indicating an established data link between the remote processor and the data bus; and

monitoring an interval between receipt of the periodic heartbeat signals,

wherein said isolating step comprises isolating the data bus from the local transceiver to alleviate the introduction of noise onto the data bus if the heartbeat signal is not received within a predetermined time interval indicating that the data link is no longer viable.

12. A method according to claim 9, wherein said monitoring step comprises monitoring data transmitted to the data bus for errors, and wherein said isolating step comprises isolating the data bus from the local transceiver when a predetermined percentage of the data received is in error to thereby alleviate the introduction of noise onto the data bus.

13. A method for establishing a data communication link between a data bus of a vehicle having a transceiver for receiving data and a remote interrogation device where unwanted signals may be received by the data bus and corrupt data on the data bus, wherein said method comprises the steps of:

connecting the local transceiver and the data bus in a data transfer mode such that the data bus may receive data transmitted by the remote interrogation device;

in the data transfer mode, initially transmitting a data link command to the data bus of the vehicle, wherein said connecting step comprises receiving the data link command and connecting the local transceiver and the data bus to thereby establish a data link between the data bus and the remote interrogation device;

periodically transmitting a heartbeat signal from the local transceiver to the remote interrogation device indicating an established data link between the remote interrogation device and the data bus;

monitoring an interval between receipt of the periodic heartbeat signal;

ceasing transmission of data from the remote interrogation device to the data bus if the heartbeat signal is not received within a predetermined time interval indicating that the data link is no longer viable; and

isolating the local transceiver from the data bus in an idle mode such that unwanted signals received by the transceiver are not input to the data bus.

14. An apparatus for establishing a data link between a data bus of one of at least two vehicles and an interrogation device having a remote processor and a remote transceiver, wherein said apparatus comprises:

a communication unit located on each of the vehicles, wherein each communication unit comprises;

a local transceiver in operable electrical communication with the data bus of the associated vehicle for transmitting data to and transmitting data from the data bus; and

a local processor in operable electrical communication with both said transceiver and the data bus;

wherein the remote processor of the interrogation device controls the remote transceiver to transmit a periodic data link command to said local processor of each of said communication units, wherein each of said local processors of each of said communication units receives the periodic data link command and compares the number of times the data link command has been received to a individual data link threshold value that differs for each vehicle, and wherein when the number of times the data link command is received is at least or great as the individual data link threshold value associated with one of the vehicles, said local processor of said communication unit associated with the vehicle forms a data link between the data bus of the vehicle and the remote processor of said interrogation device such that a data link is formed between said interrogation device and the data bus of one of the vehicles.

15. An apparatus according to claim 14, wherein each of said communication units further comprises a random number generator in electrical communication with said local processor, wherein the data link threshold value associated with each vehicle is defined by a preset number and a number generated by the random number generator associated with each vehicle, wherein the random number generator associated with each vehicle generates a random number that is added to the preset number to create an individual data link threshold value for each vehicle, wherein each of said local processors of each of said communication units receives the periodic data link command and compares the number of times the data link command has been received to the individual data link threshold value associated with the vehicle, and wherein when the number of times the data link command is received is at least or great as the individual data link threshold value associated with the vehicle, said local processor of said communication unit associated with the vehicle forms a data link between the data bus of the vehicle and the remote processor.

16. An apparatus according to claim 15, wherein the remote transceiver has a limited horizontal data transmission and reception range such that vehicles outside the transmission and reception range may receive intermittent data signals from the interrogation device.

17. An apparatus according to claim 16, wherein the remote processor of the interrogation device controls the remote transceiver to transmit a periodic data link command, wherein each data link command is transmitted at a predetermined time interval, wherein if said local processor of one of said communication units does not receive the data link command within the predetermined time interval, said local processor resets the number of times the data link command has been received, such that said local processor must receive a consecutive number of data link commands that is at least as great as the data link threshold value before forming a data link between the bus of the vehicle and the remote processor.

18. An apparatus according to claim 17, wherein the preset number portion of the individual data link threshold value for each vehicle has a selected value that is sufficiently large such that vehicles located outside the horizontal data transmission and reception range of the remote transceiver of the interrogation device that may intermittently receive the periodic data link command transmitted by the remote processor are less likely to receive the data link command consecutively enough times to exceed the individual data link threshold value associated with the vehicle than vehicles located within the transmission and reception range of the interrogation device.

19. An apparatus according to claim 16, wherein said communication unit further comprises an indicator in electrical communication with said local processor, wherein each time the local processor receives the data communication link command from the remote processor of said interrogation device, said local processor controls the indicator to indicate to a user, such that as the vehicle enters the transmission and reception range of the remote transceiver, the indicator will indicate to the user that the vehicle is in the transmission and reception range.

20. An apparatus according to claim 14, wherein the remote processor of the interrogation device ceases transmission of the data link command when a data link is formed between the data bus of one of the vehicles and the remote processor of the interrogation device, such that the communication unit of another vehicle does not attempt to establish a data link with the remote processor.

21. An apparatus according to claim 14, wherein said communication unit further comprises an indicator in electrical communication with said local processor, wherein when a data link has been established with the remote processor of the interrogation device, said local processor controls said indicator to indicate to a user that a data link has been established.

22. An apparatus according to claim 14, wherein said communication unit further comprises a switch in operable electrical communication with said local processor, said local transceiver, and the data bus of the vehicle, wherein said switch in a closed position connects said local transceiver and the data bus and in an open position isolates said local transceiver from the data bus, and wherein said local processor in a data transfer mode closes said switch and in an idle mode opens said switch such that in the idle mode unwanted signals received by said local transceiver are not input onto the data bus.

23. A method for establishing a data link between a data bus of one of at least two vehicles and an interrogation device having a remote processor and a remote transceiver, wherein said method comprises the steps of:

periodically transmitting a data link command to an individual processor associated with each data bus of each vehicle;

receiving the periodic data link command at the processor associated with each data bus;

comparing the number of times the data link command has been received by the associated processor to an individual data link threshold value associated with each vehicle; and

forming a data link between the interrogation device and the data bus of a vehicle having an associated data link threshold value that is at least or great as the number of times the data link command was received by the processor associated with the vehicle such that a data link is formed between the interrogation device and the data bus of one of the vehicles.

24. A method according to claim 23, wherein the data link threshold value associated with each vehicle is defined by a preset number and a random number, wherein said method further comprises the steps of:

individually generating a random number for each of the vehicles; and

adding the random number to the preset number to create an individual data link threshold value for each vehicle.

25. A method according to claim 23 further comprising after said forming step the step of ceasing the transmission of the data link command when said forming step forms a data link between the data bus of one of the vehicles and the remote processor of the interrogation device, such that another vehicle does not establish a data link with the remote processor.

26. A method according to claim 23, wherein the remote transceiver of the interrogation device has a limited horizontal data transmission and reception range such that vehicles outside the transmission and reception range may receive intermittent data signals from the interrogation device.

27. A method according to claim 26, wherein said transmitting step comprises transmitting a periodic data link command, wherein each data link command is transmitted at a predetermined time interval, wherein if said local processor of one of said communication units does not receive the data link command within the predetermined time interval, said method further comprises the step of resetting said counting step, such that the local processor must receive a consecutive number of data link commands that is at least or great as the data link threshold value before said forming step forms a data link between the data bus of the vehicle and the remote processor.

28. A method according to claim 27 further comprising the step of selecting a preset number portion of the individual data link threshold value for each vehicle such that the data link threshold value associated with each vehicle is sufficiently large such that vehicles located outside the horizontal data transmission and reception range of the remote transceiver of the interrogation device that may intermittently receive the periodic data link command are less likely to receive the data link command enough consecutive times to exceed the individual data link threshold value associated with the vehicle than vehicles located within the transmission and reception range of the interrogation device.

29. A method according to claim 23 further comprising the step of indicating to a user of the vehicle when said forming step forms a data link with the remote processor of the interrogation device and the data bus of the vehicle.

30. A method according to claim 23 further comprising the step of indicating to a user of the vehicle each time said receiving step receives the data communication link command, such that as the vehicle enters the transmission and reception range of the remote transceiver, said indicating step indicates to the user of the vehicle that the vehicle is in the transmission and reception range.