Tractor-trailer communication system

1. A communication system, comprising:

a trailer module disposed on a cargo trailer, the trailer module comprising a trailer identification number for the cargo trailer;

a tractor module disposed on a cargo tractor, the tractor module to electrically couple to the trailer module via a power line carrier connected between the trailer and tractor; and

power line transceivers with the trailer module and tractor module to communicate data over the power line carrier when the trailer is electrically coupled to the tractor,

wherein, when coupled to the tractor module, the trailer module communicates the trailer identification number to the tractor module over the power line carrier.

2. The communication system of claim 1 , wherein the trailer module responds to a new power line connection between the trailer and tractor by transmitting the trailer identification number to the tractor module via the power line carrier.

3. The communication system of claim 2 , wherein the trailer module waits a delay time before sending the trailer identification number to avoid transients in the power line carrier.

4. The communication system of claim 1 , wherein:

the trailer module comprises a first power line transceiver to connect the trailer module to the power line carrier;

the tractor module comprises a second power line transceiver to connect the tractor module to the power line carrier; and

each transceiver comprises:

a message handler;

a multiphase modem;

a transmit amplifier; and

a receive amplifier.

5. The communication system of claim 4 , wherein the modules are coupled to transceivers of a secondary communication protocol to connect with subsystems that communicate with a secondary communication protocol and not a power line communication protocol.

6. The communication system of claim 1 , further comprising a number of sensors disposed about the trailer coupled to the power line carrier, wherein each sensor monitors a subsystem of the cargo trailer.

7. The communication system of claim 6 , further comprising a communications bus to couple the trailer module to sensors via a different protocol than used on the power line carrier.

8. The communication system of claim 7 , wherein the second communication channel is a radio-frequency communication channel.

9. The communication system of claim 7 , wherein the second communication channel is a wired communication channel.

10. The communication system of claim 6 , wherein the number of sensors monitor at least one of:

a state of a tire inflation system;

a fuel level;

a brake pad thickness;

a tire disintegration level;

a seat belt status;

a wheel rotation count; and

a windshield wiper status.

11. The communication system of claim 1 , wherein, when coupled to the trailer module, the tractor module sends digital messages to electronic devices on the cargo trailer.

12. The communication system of claim 1 , the tractor module programmed for:

receiving an expected trailer identification number of a cargo trailer intended for the cargo tractor;

receiving the trailer identification number for the cargo trailer currently coupled to the cargo tractor; and

determining, based on a comparison of the expected trailer identification number and the current trailer identification number, when the intended cargo trailer is actually coupled to the cargo tractor.

13. The communication system of claim 12 , wherein the tractor module is further programmed for transmitting, to a remote location, an output of the comparison of the expected trailer identification number and the current trailer identification number.

14. The communication system of claim 1 , wherein the tractor module is programmed for receiving, along the power line carrier, status information from a number of subsystems of the cargo trailer in addition to the trailer identification number.

15. The communication system of claim 14 , wherein the tractor module is programmed for transmitting, to a remote location, information received from the number of subsystems of the cargo trailer.

16. The communication system of claim 1 , comprising:

the trailer module further comprising:

a first power line transceiver for communicating along a power line carrier communication network comprising the power line carrier;

the tractor module further comprising:

a second power line transceiver for communicating along the power line carrier communication network; and

a secondary transceiver for receiving information from a number of non-power line sensors;

a number of first sensors coupled to the power line carrier communication network to transmit information along the power line carrier communication network to the tractor huh regarding an associated subsystem of the cargo trailer; and

the number of non-power line sensors coupled to transmit information, via a separate communication protocol, to the trailer module secondary transceiver.

17. The communication system of claim 16 , wherein the power line carrier communication network comprises:

a physical layer of power wires;

a low level communication protocol defined by the power line transceivers; and

a higher level protocol that enables structured message communication between power line transceivers.

18. The communication system of claim 1 , wherein the trailer module further comprises:

a processor;

a memory device storing the trailer identification number for the cargo trailer; and

a transmitter to selectively transmit the trailer identification number via a short-wavelength ultra-high frequency communication protocol; and

a device detector to determine when a receiving device is within range,

wherein, when a receiving device is within range, the transmitter transmits the trailer identification number to the receiving device.

19. The communication system of claim 18 , further comprising an authenticator to authenticate the receiving device prior to transmission of the trailer identification number.

20. The communication system of claim 18 , further comprising a number of sensors disposed about the trailer coupled to the trailer module, wherein:

each sensor monitors a subsystem of the cargo trailer; and

the transmitter selectively transmits an output of the number of sensors to the receiving device when in range.

21. The communication system of claim 1 , the tractor module being programmed for:

determining, with a short-wavelength ultra-high frequency receiver, when a cargo trailer short-wavelength ultra-high frequency transceiver is within range;

when a cargo trailer transceiver is within range, extracting from the cargo trailer module a current trailer identification number for any, cargo trailer within range; and

transmitting the current trailer identification numbers associated with cargo trailers in range to a remote location.

22. The communication system of claim 21 , further comprising populating a database at the remote location with current trailer identification numbers associated with cargo trailers in range of the receiver.

23. The communication system of claim 21 , further comprising transmitting, to the remote location, at least one of a GPS location and a time stamp associated with reception of a current trailer identification number associated with each cargo trailer in range.

24. The communication system of claim 1 , further comprising a tire wear indicator comprising:

a wheel rotation counter; wherein

the communication system is coupled to the wheel rotation counter, wherein the communication system:

receives a count of wheel rotations;

calculates a number of wheel rotations per fixed distance; and

estimates tire wear from the calculated wheel rotations per mile.

25. The communication system of claim 1 , further comprising a lookup table that converts the trailer identification number to additional information about the trailer.

26. The communication system of claim 1 , wherein the tractor module is programmed to query multiple modules of the trailer in series, including the trailer module, the multiple modules connected to the power line carrier, the series of queries avoiding attempted simultaneous communication via the power line carrier.