Trailer communications system

• US 5,999,091 A
• Filed: 07/31/1997
• Issued: 12/07/1999
• Est. Priority Date: 11/25/1996
• Status: Expired due to Term

• Current Assignee: Mobile Logistics LLC
• Original Assignee: Highway Master Communications Inc.
• Inventors: Wortham, Larry C.
• Primary Examiner(s): Hofsass, Jeffery A.
• Assistant Examiner(s): TRIEU, VAN THANH
• Application Number:
  US08/904,170
• Time in Patent Office: 859 Days
• Field of Search: 340/431, 340/451, 340/452, 340/531, 340/310.02, 340/825.06, 340/989, 340/990, 340/425.5, 340/426, 340/825.54, 340/310.01
• US Class Current: 340/431
• CPC Class Codes: B60C 23/0479 Communicating with external units being not part of the vehicle, e.g. tools for diagnostic, mobile phones, electronic keys or service stations
• CPC Class Codes: G07C 5/008 communicating information to a remotely located station transmission systems for measured values G08C
• CPC Class Codes: G08G 1/123 indicating the position of vehicles, e.g. scheduled vehicles; Managing passenger vehicles circulating according to a fixed timetable, e.g. buses, trains, tramstransmission of navigation instructions to vehicles G08G1/0968
• 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

Abstract

A trailer communications system (10) includes a tag unit (26) for location on a trailer (12). A reader unit (28) can be placed at a remote location. The tag unit (26) and the reader unit (28) communicate information in response to a predetermined event which occurs substantially simultaneously at both the trailer (12) and the remote location.

Claims

1. A trailer communications system comprising:

a tag unit for location on a trailer;

a reader unit at a remote location; and

the tag unit and the reader unit operable to communicate information during a window for communication established in response to a predetermined event which occurs substantially simultaneously at both the trailer and the remote location, wherein the information communicated between the tag unit and the reader unit outside the window is considered invalid.

2. The system of claim 1, wherein the remote location comprises a vehicle coupled to the trailer.

3. The system of claim 2, wherein the predetermined event comprises an event supported by a seven-pin connector between the trailer and the vehicle.

4. The system of claim 2, wherein the predetermined event comprises the application of brakes on the trailer and the vehicle.

5. The system of claim 1, further comprising at least one sensor located on the trailer and coupled to the tag unit, the sensor operable to monitor at least one of temperature, humidity, and pressure within the trailer.

6. The system of claim 1, wherein the tag unit comprises:

a memory operable to store information relating to the trailer;

a detector operable to detect the predetermined event; and

a transmitter coupled to the memory and the detector, the transmitter operable to transmit the information stored in the memory in response to the detection of the predetermined event.

7. The system of claim 1, wherein the tag unit operates in an inactive mode to conserve power and an active mode to communicate information.

8. The system of claim 7, wherein the tag unit comprises:

a detector operable to detect the predetermined event; and

a processor coupled to the detector, the processor operable to transition the tag unit from the inactive mode to the active mode in response to the detection of the predetermined event.

9. The system of claim 1, wherein each of the tag unit and the reader unit communicates using radio frequency.

10. The system of claim 1, wherein the predetermined event comprises one of a synchronization event, a ping event, an alarm event, or the lapse of a predetermined interval.

11. The system of claim 1, further comprising a relay unit in communication with the reader unit, the relay unit operable to relay the information communicated between the tag unit and the reader unit to a host.

12. The system of claim 11, wherein the relay unit is further operable to provide positioning information for locating the trailer.

13. The system of claim 1, wherein the tag unit comprises at least one control interface operable to provide control information to at least one conditioning device on the trailer.

14. The system of claim 13, wherein the control interface provides control information to at least one of a refrigeration unit, a humidifier, and an anti-shock device.

15. The system of claim 1, wherein the window for communication is initiated by a first synchronization event and is terminated by a second synchronization event.

16. The system of claim 1, wherein:

the tag unit comprises a particular one of a number of tag units;

the window for communication is associated with the particular tag unit;

the information comprises first data having an identifier associated with the particular tag unit and second data not having an identifier associated with the particular tag unit; and

the second data not having an identifier associated with the particular tag unit is considered invalid.

17. The system of claim 1, wherein the tag unit comprises a first tag unit and the information communicated by the first tag unit to the reader unit comprises information communicated to the first tag unit by a second tag unit located on a second trailer.

18. A tag unit for location on a trailer, the tag unit operating in either an inactive mode or an active mode, the tag unit comprising:

a memory operable to store information relating to the trailer;

an activating event detector operable to detect an activating event which occurs substantially simultaneously at the trailer and a remote location;

a processor coupled to the memory and the activating event detector, the processor operable to transition the tag unit from inactive mode to active mode in response to the detection of an activating event; and

a transmitter coupled to the processor, the transmitter operable to transmit the information stored in the memory during a window for communication established in response to the detection of the activating event by the activating event detector, wherein the information communicated between the tag unit and the remote location outside the window is considered invalid.

19. The tag unit of claim 18, further comprising at least one sensor interface, the sensor interface operable to relay information generated by a sensor to the processor.

20. The tag unit of claim 19, wherein the sensor monitors at least one of temperature, humidity, and pressure within the trailer.

21. The tag unit of claim 18, wherein the activating event detector comprises one of a synchronization event detector, a ping event detector, or a sensor interface.

22. The tag unit of claim 18, wherein the activating event comprises an event supported by a seven-pin connector between the trailer and the vehicle.

23. The tag unit of claim 18, wherein the activating event comprises one of a synchronization event, a ping event, an alarm event, or the lapse of a predetermined interval.

24. The tag unit of claim 18, wherein the transmitter communicates using radio frequency.

25. The tag unit of claim 18, further comprising at least one control interface operable to provide control information to at least one conditioning device on the trailer.

26. The tag unit of claim 25, wherein the control interface provides control information to at least one of a refrigeration unit, a humidifier, and an anti-shock device.

27. The tag unit of claim 18, wherein the window for communication is initiated by a first synchronization event and is terminated by a second synchronization event.

28. The tag unit of claim 18, wherein the tag unit comprises a first tag unit and the information comprises information communicated to the first tag unit by a second tag unit located on a second trailer.

29. A method for communicating with a trailer comprising:

detecting a predetermined event which occurs substantially simultaneously at both the trailer and a remote location;

specifying a window for communication between a tag unit on the trailer and a reader unit at the remote location in response to the detection of the predetermined event; and

communicating information from the tag unit to the reader unit, wherein information communicated between the tag unit and the reader unit outside the window is considered invalid.

30. The method of claim 29, wherein the remote location comprises a vehicle coupled to the trailer.

31. The method of claim 30, wherein the predetermined event comprises an event supported by a seven-pin connector between the trailer and the vehicle.

32. The method of claim 30, wherein the predetermined event comprises the application of brakes on the trailer and the vehicle.

33. The method of claim 29, further comprising the step of transitioning the tag unit from an inactive mode to an active mode in response to the detection of the predetermined event.

34. The method of claim 29, wherein the information comprises control information, and further comprising communicating the control information from the tag unit to a conditioning device on the trailer.

35. The method of claim 29, wherein:

the predetermined event comprises a first synchronization event and a second synchronization event; and

the step of specifying a window for communication comprises initiating the window for communication in response to the first synchronization event and terminating the window for communication in response to the second synchronization event.

36. The method of claim 29, wherein:

the tag unit comprises a particular one of a number of tag units;

the window for communication is associated with the particular tag unit;

the information comprises first data having an identifier associated with the particular tag unit and second data not having an identifier associated with the particular tag unit; and

the second data not having an identifier associated with the particular tag unit is considered invalid.

37. The method of claim 29, wherein the tag unit comprises a first tag unit and the information communicated by the first tag unit to the reader unit comprises information communicated to the first tag unit by a second tag unit located on a second trailer.