Vehicle communication system using incompatible modulation techniques

{
  "publication_number": "US10623216B1",
  "country": "US",
  "kind": "B1",
  "title": "Vehicle communication system using incompatible modulation techniques",
  "abstract": "A locomotive communication system includes a lead communication device wirelessly communicating command messages to remote communication devices onboard a rail vehicle system during a messaging cycle. The lead device receives reply messages from the remote devices during the messaging cycle in response to the command messages. The lead device receives a status signal from at least one of the remote devices during a guard interval that follows completion of the messaging cycle. The lead device communicates the command message and receives the reply messages using analog modulation or digital modulation. The lead communication device also receives the status signal using the other of the analog modulation or the digital modulation. The command messages, the reply messages, and the status signal are communicated using a designated frequency channel.",
  "claims": [
    "1. A vehicle communication system comprising: a lead communication device configured to wirelessly communicate a command message to one or more remote communication devices onboard a vehicle system during a messaging cycle, the lead communication device configured to receive one or more reply messages from the one or more remote communication devices during the messaging cycle in response to communicating the command message, the lead communication device also configured to receive a status signal from at least one of the remote communication devices during a guard interval that follows completion of the messaging cycle, wherein the lead communication device is configured to communicate the command message and receive the one or more reply messages using a first modulation, wherein the lead communication device is configured to receive the status signal using a different, second modulation, wherein the lead communication device is configured to communicate the command message and receive the one or more reply messages and the status signal using a designated frequency channel, and wherein the lead communication device is configured to send one or more of a throttle command or a brake command to the one or more remote vehicles in the command message sent during the messaging cycle, the lead communication device is configured to receive a confirmation that the one or more remote vehicles received the one or more of the throttle command or the brake command in the one or more reply messages during the messaging cycle, and the lead communication device is configured to receive sensor data from at least one of the one or more remote vehicles in the status signal during the guard interval.",
    "2. The vehicle communication system of claim 1, wherein the first modulation is frequency shift key modulation.",
    "3. The vehicle communication system of claim 1, wherein the second modulation is phase shift key modulation.",
    "4. The vehicle communication system of claim 1, wherein the designated frequency channel is a single frequency.",
    "5. The vehicle communication system of claim 1, wherein the lead communication device is configured to send the command message during the messaging cycle using frequency shift key modulation and using a communication channel that consists of a single frequency, the lead communication device also configured to receive the status signal during the guard interval using phase shift key modulation and using the communication channel that consists of the single frequency, and the lead communication device is configured to receive the one or more reply messages during the messaging cycle using the communication channel that consists of the single frequency.",
    "6. The vehicle communication system of claim 1, wherein the lead communication device is configured to not send any signal using the first modulation during the guard interval that follows the messaging cycle.",
    "7. The vehicle communication system of claim 1, wherein the lead communication device is configured to be disposed onboard a lead vehicle in a vehicle system and the one or more remote communication devices are configured to be disposed onboard one or more remote vehicles in the vehicle system.",
    "8. A method comprising: wirelessly communicating a command message from a lead communication device to one or more remote communication devices onboard a vehicle system during a messaging cycle; wirelessly receiving one or more reply messages from the one or more remote communication devices during the messaging cycle in response to communicating the command message; and wirelessly receiving a status signal from at least one of the remote communication devices during a guard interval that follows completion of the messaging cycle, wherein the command message and the reply message are communicated using a first modulation, wherein the status signal is received using a different, second modulation, wherein the command message, the reply message, and the status signal are communicated using a designated frequency channel, and wherein the command message includes one or more of a throttle command or a brake command for one or more remote vehicles in the vehicle system, the reply message includes a confirmation that the one or more remote vehicles received the one or more of the throttle command or the brake command, and the status signal includes sensor data from at least one of the one or more remote vehicles.",
    "9. The method of claim 8, wherein the first modulation is frequency shift key modulation.",
    "10. The method of claim 8, wherein the second modulation is phase shift key modulation.",
    "11. The method of claim 8, wherein the designated single frequency channel is a single frequency.",
    "12. The method of claim 8, wherein the command message is communicated during the messaging cycle using frequency shift key modulation and using a communication channel that consists of a single frequency, the status signal is received during the guard interval using phase shift key modulation and using the communication channel that consists of the single frequency, and the reply message is received during the messaging cycle using the communication channel that consists of the single frequency.",
    "13. The method of claim 8, wherein the first modulation is not used to communicate any message during the guard interval that follows the messaging cycle.",
    "14. A vehicle communication system comprising: a lead communication device configured to be disposed onboard a lead vehicle of a vehicle system; wherein the lead communication device is configured to communicate with one or more remote communication devices according to a defined messaging cycle to control movement of the vehicle system, the one or more remote communication devices disposed onboard one or more remote vehicles in the vehicle system, the messaging cycle including a first time slot for the lead communication device to send a command signal to the one or more remote communication devices using a first modulation scheme on a single frequency channel and one or more subsequent second time slots for the one or more remote communication devices to send a reply signal to the lead communication device using the first modulation scheme on the single frequency channel, wherein the lead communication device is configured to receive a status signal from at least one of the remote communication devices using a second modulation scheme on the single frequency channel, wherein the first modulation scheme and the second modulation scheme are incompatible with each other, and wherein the status signal includes sensor data.",
    "15. The vehicle communication system of claim 14, wherein the lead communication device is configured to receive the status signal only during a guard interval that follows the messaging cycle and during which no other vehicle system is able to use the single frequency channel for communication.",
    "16. The vehicle communication system of claim 14, wherein the first modulation scheme is an analog modulation scheme and the second modulation scheme is a digital modulation scheme.",
    "17. The vehicle communication system of claim 14, wherein the command signal directs a change in one or more of a throttle setting or a brake setting of the one or more remote vehicles."
  ],
  "description_excerpt": "The subject matter described herein relates to locomotive communication systems.\n\nVehicle systems can have multiple propulsion-generating vehicles that include communication devices for the vehicles to communicate with each other. The vehicles can communicate with each other to coordinate individual vehicle movements so that the entire vehicle system moves along routes. For example, locomotives can communicate with each other using wireless communications so that one locomotive can remotely direct the throttle settings, brake settings, etc., of the other locomotives in the same rail vehicle system.\n\nThe locomotives may send messages (also referred to as signals) back-and-forth to ensure that messages commanding changes in throttle settings and/or brake settings are sent and that messages indicating the changes were received are sent. These vehicle systems typically employ a contention scheme to prevent overlapping interference between the different messages. For example, some locomotives use a slotted aloha protocol to allow multiple trains containing multiple locomotives to use the same frequency channel for communicating messages between the locomotives in the same train. This protocol divides the times at which different locomotives can communicate over the channel into time slots that are accessed on a prioritized but randomized basis.\n\nOnce a lead locomotive from a one train seizes the channel, that lead locomotive and the remote locomotives that are controlled by that lead locomotive have exclusivity of the channel for a defined period of time.",
  "cpc": [
    "H04L 27/0008",
    "B61C 17/12",
    "B61L 15/0027",
    "B61L 15/0036",
    "B61L 15/0062",
    "B61L 3/008",
    "B61L 3/127",
    "H04L 27/12",
    "H04L 27/2035",
    "Y02T 30/00"
  ],
  "ipc": [
    "B61L 15/00",
    "B61L 3/00",
    "H04B 7/26",
    "H04L 27/00",
    "H04L 27/12",
    "H04L 27/20"
  ],
  "assignees": [
    "GE Global Sourcing LLC"
  ],
  "inventors": [
    "Gary William Mason",
    "Maurice HUTCHINS",
    "Robert Palanti"
  ],
  "filing_date": "2018-11-08",
  "publication_date": "2020-04-14",
  "grant_date": "2020-04-14",
  "priority_date": "2018-11-08",
  "application_number": "US-201816184804-A",
  "family_id": "70223566",
  "cited_by_count": 2,
  "citations": [
    "US20040120305A1",
    "US7395141B1",
    "US8310979B2",
    "US8914167B2",
    "US20150229502A1",
    "US20180049067A1",
    "US20180062902A1"
  ]
}