On-board message repeater for railroad train communications system

• US 20060085103A1
• Filed: 03/23/2005
• Published: 04/20/2006
• Est. Priority Date: 04/26/2004
• Status: Active Grant

• Current Assignee: GE Global Sourcing LLC (Westinghouse Air Brake Technologies Corporation)
• Original Assignee: General Electric Company
• Inventors: Peltz, David Michael, Palanti, Robert C., Smith, Eugene A. Jr.
• Granted Patent: US 7,664,459 B2
• Time in Patent Office: Days
• US Class Current: 701/19
• CPC Class Codes: B61L 15/0027 Radio-based, e.g. using GSM-R
• CPC Class Codes: B61L 27/20 Trackside control of safe travel of vehicle or train, e.g. braking curve calculation
• CPC Class Codes: H04B 7/0608 Antenna selection according to transmission parameters
• CPC Class Codes: H04B 7/0802 using antenna selection H04B7/0868 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels

Abstract

A distributed power train (10) communications system for sending and receiving signals between a lead locomotive (14) and remote locomotives (12A/12B/12C) in the train (10). A lead (14) initiated message is received by at least the remote locomotive (12A/12B) nearest to the lead unit (14). The receiving remote unit (12A/12B) retransmits the message for receiving by the next remote unit (12C) in the train. Thus the message leapfrogs down the train from the lead unit (14) to the remote units (12A/12B/12C). When the last remote unit (the nth remote unit) (12C) receives the message, the last remote (12C) transmits a status or other response message to the lead unit'"'"'s message. The status message is received at the (n-1)th remote unit (12A/12B), which appends its status message and transmits the combined status messages toward the lead unit (14). Each successive remote unit receives the status messages of the other remote units and appends its status message, until the concatenated status message reaches the lead unit (14).

Claims

1. A communications method for a railroad train comprising a lead locomotive and at least two remote locomotives, the method comprising:

transmitting an outbound message from the lead locomotive;

for each remote locomotive, receiving the outbound message from the lead locomotive or from another remote locomotive and transmitting the outbound message until the outbound message has been received by a last remote locomotive;

at the last remote locomotive, transmitting an inbound message responsive to the outbound message; and

for each remote locomotive except the last remote locomotive, receiving the inbound message from another remote locomotive, appending a local status message and transmitting a modified inbound message until the modified inbound message has been received by the lead locomotive.

2. The communications method of claim 1 wherein the outbound message comprises a command message or a status update message.

3. The communications method of claim 1 wherein the inbound message comprises a status message indicating a status of the last remote locomotive, and wherein the local status message comprises a status message indicating a status of the remote locomotive appending the local status message.

4. The communications method of claim 1 wherein the outbound message is received by each remote locomotive prior to the modified inbound message reaching the lead locomotive.

5. The communications method of claim 1 wherein the step of for each remote locomotive receiving the outbound message, further comprises receiving the outbound message from the lead locomotive or from another remote locomotive and successively transmitting the outbound message for receiving by a next consecutive remote locomotive in the direction away from the lead locomotive until the outbound message has been received by the last remote locomotive.

6. The communications method of claim 1 wherein the step of for each remote locomotive, receiving the outbound message, further comprises receiving the outbound message from the lead locomotive or from another remote locomotive, waiting a predetermined time and transmitting the outbound message for receiving by a next consecutive remote locomotive in the direction away from the lead locomotive until the outbound message has been received by the last remote locomotive.

7. The communications method of claim 1 wherein the step of for each remote locomotive except the last remote locomotive, receiving the inbound message, further comprises receiving the inbound message from another remote locomotive, appending a local status message to the inbound message and transmitting the modified inbound message for receiving by a next consecutive remote locomotive in the direction toward the lead locomotive until the modified inbound message has been received by the lead locomotive.

8. The communications method of claim 7 wherein the step of for each remote locomotive except the last remote locomotive, receiving the inbound message, further comprises receiving the inbound message, appending a local status message to the inbound message, waiting a predetermined time and transmitting the modified inbound message for receiving by a next consecutive remote locomotive in the direction toward the lead locomotive until the modified inbound message has been received by the lead locomotive.

9. The communications method of claim 1 further comprising receiving the modified inbound message at the lead locomotive, wherein the modified inbound message comprises a concatenated status message further comprising the local status message of each remote locomotive.

10. The communications method of claim 9 wherein the local status message of each remote locomotive further comprises an indication of the response at the respective remote locomotive to the outbound message.

11. A communications method for a railroad train comprising a lead locomotive and at least two remote locomotives, wherein the lead locomotive transmits standard outbound messages and priority outbound messages intended for at least one remote locomotive and the remote locomotives transmit an inbound status message intended for the lead locomotive, the method comprising:

for a standard outbound message;

transmitting the outbound message from the lead locomotive;

receiving the outbound message at one or more of the remote locomotives;

at each remote locomotive receiving the outbound message, transmitting an inbound status message intended for the lead locomotive and retransmitting the outbound message, wherein the remote locomotives transmit the inbound status message and retransmits the outbound message in an order determined by a location of the remote locomotive relative to the lead locomotive, with a remote locomotive nearest the lead locomotive first transmitting the inbound status message and retransmitting the outbound message;

for a priority outbound message;

transmitting the outbound message from the lead locomotive;

receiving the outbound message at one or more of the remote locomotives;

at each remote locomotive receiving the outbound message, retransmitting the outbound message in an order determined by a location of the remote locomotive relative to the lead locomotive, with a remote locomotive nearest the lead locomotive first retransmitting the outbound message;

at the last remote locomotive, in response to receiving the outbound message transmitting an inbound message responsive to the outbound message;

at each remote locomotive receiving the inbound message, appending a local status message and transmitting a modified inbound message comprising the inbound message and the local status message in an order determined by a location of the remote locomotive relative to the lead locomotive, with a remote locomotive farthest from the lead locomotive first transmitting the modified inbound message;

receiving the modified inbound message at the lead locomotive.

12. The communications method of claim 11 wherein each remote locomotive retransmits the outbound message at a time determined by when another remote locomotive closer to the lead locomotive retransmitted the outbound message.

13. The communications method of claim 11 wherein each remote locomotive retransmits the modified inbound message at a time determined by when another remote locomotive farther from the lead locomotive transmitted the modified inbound message.

14. The communications method of claim 11 further comprising determining an operating condition of the train, and determining whether the outbound message comprises the standard outbound message or the priority outbound message in response to the operating condition.

15. The communications method of claim 14 wherein the step of determining the operating condition of the train further comprises determining that the lead locomotive can communicate with each of the remote locomotives and in response thereto the outbound message comprises the standard outbound message.

16. A communications method for a railroad train comprising a lead locomotive and remote locomotives, the method comprising:

transmitting an outbound message from the lead locomotive;

for each remote locomotive, receiving the outbound message from the lead locomotive or from another remote locomotive and transmitting the outbound message for receiving by the remote locomotives in a direction away from the lead locomotive until the outbound message is received by a last remote locomotive;

at the last remote locomotive, transmitting an inbound message responsive to the outbound message and transmitting the outbound message; and

for each remote locomotive except the last remote locomotive, receiving the inbound message from another remote locomotive, appending a local status message, and transmitting a modified inbound message and the outbound message for receiving by the remote locomotives until the modified inbound message is received by the lead locomotive.

17. The communications method of claim 16 wherein the lead locomotive retransmits the outbound message if one or more of the remote locomotives did not receive the outbound message as determined from a content of the modified inbound message received by the lead locomotive.

18. A communications method for a railroad train comprising a lead locomotive and at least two remote locomotives and a communications system over which the lead and the remote locomotives communicate, the method comprising:

transmitting an outbound message from the lead locomotive;

receiving the outbound message at one or more of the remote locomotives;

transmitting the outbound message from the one or more remote locomotives that received the outbound message in an order determined by increasing distance between the lead locomotive and the remote locomotive beginning with the remote locomotive having the shortest distance, and wherein each remote locomotive transmits the outbound message a predetermined time after a previous remote locomotive or the lead locomotive transmitted the outbound message;

from the remote locomotive most distant from the lead locomotive, in response to receiving the outbound message, transmitting an inbound message;

receiving the inbound message at one or more of the remote locomotives;

transmitting a modified inbound message from the one or more remote locomotives that received the inbound message in an order determined by decreasing distance between the lead locomotive and the remote locomotive beginning with the remote locomotive having the greatest distance, and wherein the modified inbound message comprises the inbound message and a local status message of the remote locomotive, and wherein each remote locomotive transmits the modified inbound message a predetermined time interval after the previous remote locomotive retransmitted the modified inbound message.

19. A communications method for a railroad train comprising a lead consist comprising a forward and a rearward locomotive and a remote consist comprising a forward and a rearward locomotive, wherein each of the forward and the rearward locomotives of each of the lead and the remote consists comprises an antenna and an associated radio, the method comprising:

transmitting an outbound message from the lead consist;

at the remote consist, receiving the outbound message at the antenna of the forward locomotive and supplying the received signal to the associated radio for producing a first received signal, and receiving the outbound message at the antenna of the rearward locomotive and supplying the received signal to the associated radio for producing a second received signal;

determining a first signal quality metric of the first signal;

determining a second signal quality metric of the second signal; and

selecting the first or the second received signal for processing by the remote consist in response to the first and the second signal quality metrics.

20. The communications method of claim 19 wherein the signal quality metric comprises one of a signal strength, bit error rate and signal-to-noise ratio.

21. The communications method of claim 19 wherein the step of determining the first signal quality metric further comprises determining the first signal quality metric from a segment of the first signal, and wherein the step of determining the second signal quality metric further comprises determining the second signal quality metric from a segment of the second signal.

22. The communications method of claim 19 further comprising:

transmitting an inbound message from the remote consist;

at the lead consist, receiving the inbound message at the antenna of the forward locomotive and supplying the received signal to the associated radio for producing a third received signal, and receiving the outbound message at the antenna of the rearward locomotive and supplying the received signal to the associated radio for producing a fourth received signal;

determining a third signal quality metric of the third signal;

determining a fourth signal quality metric of the fourth signal; and

selecting the third or the fourth received signal for processing by the lead consist in response to the third and the fourth signal quality metrics.

23. A communications method for a railroad train comprising a lead locomotive and at least two remote consists each remote consist comprising a forward and a rearward locomotive, wherein each of the forward, the rearward and the lead locomotives comprises an antenna and an associated radio for transmitting and receiving signals over a communications channel, the method comprising:

at one of the remote consists;

producing a signal to be transmitted over the communications channel;

determining an intended radio for receiving the signal; and

transmitting the signal from the forward locomotive or the rearward locomotive in response to the determining step.

24. The communications method of claim 23 wherein the step of transmitting further comprises transmitting from a one of the forward locomotive or the rearward locomotive that is closest to the intended radio for receiving the signal.

25. The communications method of claim 23 wherein the step of determining further comprises determining that the intended radio is in an inbound direction or an outbound direction from the one remote consist, and the step of selecting further comprises selecting the forward locomotive to transmit an inbound signal and selecting the rearward locomotive to transmit an outbound signal.

26. A communications system for a railroad train having a lead locomotive and at least two remote locomotives, the communications system comprising:

a communications channel;

a radio in the lead locomotive for transmitting an outbound message over the communications channel for receiving by the remote locomotives;

a radio in each remote locomotive for receiving the outbound message and transmitting the outbound message over the communications channel for receiving by remote locomotives more distant from the lead locomotive, wherein the radio in each remote locomotive may not receive the outbound message;

a radio in a last remote locomotive for receiving the outbound message from the lead locomotive or from another remote locomotive and for transmitting an inbound message in response to the outbound message over the communications channel for receiving by remote locomotives closer to the lead locomotive and for receiving by the lead locomotive, wherein the radio in the lead locomotive and the radio in each remote locomotive may not receive the inbound message;

wherein the radio in each remote locomotive receiving the inbound message appends a local status message thereto to form a modified inbound message and transmits the modified inbound message over the communications channel for receiving by another remote locomotive or by the lead locomotive.

27. The communications system of claim 26 wherein the outbound message comprises a command message or a status update message.

28. The communications system of claim 26 wherein the inbound message comprises a status message indicating a status of the last remote locomotive, and wherein the local status message comprises a status message indicating a status of the remote locomotive appending the local status message.

29. The communications system of claim 26 wherein the outbound message is received by the radio in each remote locomotive prior to receiving of the modified inbound message at the lead locomotive.

30. The communications system of claim 26 wherein the modified inbound message comprises a concatenated status message further comprising the local status message of each remote locomotive.

31. The communications system of claim 26 wherein the local status message of each remote locomotive further comprises an indication of the response at the respective remote locomotive to the outbound message.

32. The communications system of claim 26 wherein the radio in each remote locomotive receiving the inbound message appends a local status message thereto to form a modified inbound message and transmits the modified inbound message and the outbound message over the communications channel for receiving by another remote locomotive or by the lead locomotive.

33. A communications system for a railroad train having a lead consist and a remote consist comprising a forward locomotive and a rearward locomotive, the communications system comprising:

a communications channel;

a radio in the lead consist for transmitting an outbound message over the communications channel for receiving by the remote consist;

a radio in each of the forward and the rearward locomotives both receiving the outbound message, wherein the radio in the forward locomotive determines a signal quality metric of a forward received signal, and wherein the radio in the rearward locomotive determines a signal quality metric of a rearward received signal;

a comparator for comparing the signal quality metric of the forward and the rearward received signals;

a processor for processing the forward received signal or the rearward received signal having a better signal quality metric.

34. The communications system of claim 33 wherein the signal quality metric comprises one of a signal strength, bit error rate and signal-to-noise ratio.

35. The communications system of claim 33 wherein the radio in the forward locomotive determines the signal quality metric of the forward received signal from a segment of the forward received signal, and wherein the radio in the rearward locomotive determines the signal quality metric of the rearward received signal from a segment of the rearward received signal.

36. The communications system of claim 33 wherein the lead consist comprises a forward locomotive and a rearward locomotive, the communications system further comprising:

a radio in each of the forward and the rearward locomotives of the lead consist both receiving an inbound message from the remote consist, wherein the radio in the forward locomotive of the lead consist determines a signal quality metric of a forward received signal, and wherein the radio in the rearward locomotive of the lead consist determines a signal quality metric of a rearward received signal;

a comparator for comparing the signal quality metric of the forward and the rearward received signals;

a processor for processing the forward received signal or the rearward received signal having a better signal quality metric.

37. A communications system for a railroad train comprising a lead locomotive and at least two remote consists each remote consist comprising a forward locomotive and a rearward locomotive, the communications system comprising:

a communications channel;

an antenna at each of the forward locomotives, the rearward locomotives and the lead locomotive;

a radio at each of the forward locomotives, the rearward locomotives and the lead locomotive, wherein the radio is operative with an associated antenna for transmitting and receiving signals over the communications channel;

a station at one remote consist for producing a signal to be transmitted to another remote consist or to the lead locomotive; and

a processor for determining an intended radio for receiving the signal and for selecting one of the radio at the forward locomotive or the radio at the rearward locomotive for sending the signal in response to the intended radio for receiving the signal.

38. The communications system of claim 37 wherein the processor selects one of the radio at the forward locomotive or the radio at the rearward locomotive that is closest to the intended radio for receiving the signal.

39. The communications system of claim 37 wherein the processor determines that the intended radio for receiving the signal is in an inbound direction or an outbound direction from the one remote consist, and the processor selects the forward locomotive to transmit an inbound signal and selects the rearward locomotive to transmit an outbound signal.

40. A computer program product for operating a communications system for a railroad train comprising a lead locomotive and a remote consist comprising a forward and a rearward locomotive, wherein a signal is transmitted from the lead locomotive and in response thereto a forward received signal is received at the forward locomotive and a rearward received signal is received at the rearward locomotive, the computer program product comprising:

a computer usable medium having computer readable program code modules embodied in the medium for operating the communications system;

a computer readable first program code module for determining a forward signal quality metric of the forward received signal;

a computer readable second program code module for determining a rearward signal quality metric of the rearward received signal; and

a computer readable third program code module for selecting the forward or the rearward received signal in response to the forward and the rearward signal quality metrics.

41. A computer program product for operating a communications system for a railroad train comprising a lead locomotive and at least two remote consists each remote consist comprising a forward and a rearward locomotive, wherein each of the forward, the rearward and the lead locomotives comprises an antenna and an associated radio for transmitting and receiving signals over a communications channel, the computer program product comprising:

a computer usable medium having computer readable program code modules embodied in the medium for operating the communications system at one of the remote consists;

a computer readable first program code module for producing a signal to be transmitted over the communications channel;

a computer readable second program code module for determining an intended radio for receiving the signal; and

a computer readable third program code module for transmitting the signal from the forward locomotive or the rearward locomotive in response to the intended radio for receiving the signal.