On-board message repeater for railroad train communications system

• US 7,664,459 B2
• Filed: 03/23/2005
• Issued: 02/16/2010
• 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: Smith, Eugene A. Jr., Peltz, David Michael, Palanti, Robert C.
• Primary Examiner(s): Dean; Raymond S
• Application Number:
  US11/088,090
• Publication Number:
  US 20060085103A1
• Time in Patent Office: 1,791 Days
• Field of Search: 455 7- 111, 455/18, 455/24, 340/298, 701 19- 20, 370/315, 2461661-173
• US Class Current: 455/7
• 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 receiving by all remote locomotives that are within communications range of the lead locomotive;

at each remote locomotive that receives the outbound message, storing the outbound message, and transmitting the outbound message during an outbound time slot defined for the receiving remote locomotive, wherein each remote locomotive transmits the outbound message before transmitting an inbound message;

at a remote locomotive configured as the last locomotive, receiving the outbound message, and transmitting an inbound message comprising a response of the last remote locomotive to the outbound message;

at each remote locomotive that receives the inbound message, except the last remote locomotive, storing the inbound message, appending a local status message and transmitting a modified inbound message during an inbound time slot defined for the receiving locomotive, wherein the inbound message that reaches the lead locomotive comprises a response to the outbound message from each remote locomotive that received the outbound message;

at the lead locomotive, determining whether a reply was received from all remote locomotives, and in the event a reply was not received from one or more of the remote locomotives transmitting the outbound message again;

wherein the outbound time slots and the inbound time slots are responsive to a number of remote locomotives in the train and a time slot is assigned to each remote locomotive based on a position of the remote locomotive in the train; and

wherein a beginning time of an outbound and an inbound time slot for a remote locomotive is modified if one or more other remote locomotives do not transmit an outbound message or do not transmit an inbound message.

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

3. The communications method of claim 1 wherein the response of the last locomotive to the outbound message comprises a status message indicating a status of the last remote locomotive, and wherein the response of each remote locomotive that received the outbound message comprises a status message indicating a status of the remote locomotive receiving the outbound message.

4. The communications method of claim 1 wherein the step of at each remote locomotive that receives the outbound message, further comprises receiving the outbound message from the lead locomotive or from another remote locomotive.

5. The communications method of claim 1 wherein the step of at each remote locomotive that receives the inbound message, except the last remote locomotive, further comprises receiving the inbound message from the remote locomotive configured as the last locomotive or from another remote locomotive.

6. 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 a local status message of each remote locomotive.

7. The communications method of claim 6 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.

8. 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 for receiving by all remote locomotives that are within communications range of the lead locomotive;

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

at each remote locomotive receiving the outbound message, storing the outbound message, and retransmitting the outbound message during an outbound timeslot defined for the receiving remote locomotive, wherein each remote locomotive transmits the outbound message before transmitting an inbound 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, except the last remote locomotive, storing the inbound message, appending a local status message and transmitting a modified inbound message during an inbound timeslot defined for the receiving locomotive;

receiving the modified inbound message at the lead locomotive, wherein the inbound message that reaches the lead locomotive comprises a response to the outbound message from each remote locomotive that received the outbound message;

at the lead locomotive, determining whether a reply was received from all remote locomotives, and in the event a reply was not received from one or more of the remote locomotives transmitting the outbound message again;

wherein the outbound time slots and the inbound time slots are responsive to a number of remote locomotives in the train and a time slot is assigned to each remote locomotive based on the position of the remote locomotive in the train; and

wherein a beginning time of an outbound and an inbound time slot for a remote locomotive is modified if one or more other remote locomotives do not transmit an outbound message or do not transmit an inbound message.

9. The communications method of claim 8 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.

10. The communications method of claim 8 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.

11. The communications method of claim 8 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.

12. The communications method of claim 11 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.

13. 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 for receiving by all remote locomotives;

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

storing the outbound message at the receiving outbound locomotives;

transmitting the outbound message from the receiving outbound locomotives, in an order determined by increasing distance between the lead locomotive and the remote locomotive beginning with transmitting the remote locomotive having the shortest distance, and wherein each receiving outbound locomotive transmits the outbound message during an outbound time slot defined for the receiving outbound locomotive, wherein each remote locomotive transmits the outbound message before transmitting an inbound 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 receiving inbound locomotives of the one or more remote locomotives;

transmitting a modified inbound message from the receiving inbound locomotives in an order determined by decreasing distance between the lead locomotive and the remote locomotive beginning with transmitting from the remote locomotive having the greatest distance, and wherein the modified inbound message comprises the modified inbound message as received plus a local status message of the receiving inbound locomotive appended thereto, and wherein each receiving inbound locomotive transmits the modified inbound message during an inbound timeslot defined for the receiving inbound locomotive;

at the lead locomotive, determining whether a reply was received from all remote locomotives, and in the event a reply was not received from one or more of the remote locomotives transmitting the outbound message again;

wherein the outbound time slots and the inbound time slots are responsive to a number of remote locomotives in the train and a time slot is assigned to each remote locomotive based on the position of the remote locomotive in the train; and

wherein a beginning time of an outbound and an inbound time slot for a remote locomotive is modified if one or more other remote locomotives do not transmit an outbound message or do not transmit an inbound message.

14. 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 all of the remote locomotives that are within communications range of the lead locomotive;

a radio in each remote locomotive for receiving the outbound message, each remote locomotive receiving the outbound message storing the outbound message and transmitting the outbound message over the communications channel during an outbound time slot defined for the receiving locomotive, wherein each remote locomotive transmits the outbound message before transmitting an inbound message;

a radio in a last remote locomotive for receiving the outbound message and for transmitting an inbound message comprising a response of the last remote locomotive to the outbound message over the communications channel;

wherein the radio in each remote locomotive receiving the inbound message, except the last remote locomotive, stores the inbound message and appends a local status message thereto to form a modified inbound message and transmits the modified inbound message over the communications channel during an inbound time slot defined for the receiving locomotive, wherein the inbound status message that reaches the lead locomotive comprises a response to the outbound message from each remote locomotive that received the outbound message, the lead locomotive determining whether a reply was received from all remote locomotives, and in the event a reply was not received from one or more of the remote locomotives, transmitting the outbound message again;

wherein the outbound time slots and the inbound time slots are responsive to a number of remote locomotives in the train and a time slot is assigned to each remote locomotive based on a position of the remote locomotive in the train; and

wherein a beginning time of an outbound and an inbound time slot for a remote locomotive is modified if one or more other remote locomotives do not transmit an outbound message or do not transmit an inbound message.

15. The communications system of claim 14 wherein the outbound message comprises a command message or a status update message.

16. The communications system of claim 14 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.

17. The communications system of claim 14 wherein the modified inbound message comprises a concatenated status message further comprising the local status message of each remote locomotive that received the outbound message.

18. The communications system of claim 14 wherein the local status message of each remote locomotive further comprises an indication of a response at the respective remote locomotive to the outbound message.