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            Acoustical Warning Device for Locomotive Horns
      

      
  Document Series
              Technical Reports


      
  Author
          Federal Railroad Administration


      
Report Number
              DOT/FRA/ORD-22/08

  Office
              RDI-22


      Subject
                    Grade Crossing Technology


      
  Keywords
              Acoustic Warning Device, AWD, air horn, variable directivity, grade crossing, sound beam steering, speaker array, locomotive, detectability, noise reduction


      

      
      
              
                  
      
              
  Document
              AWD for Locomotive Horns.pdf (4.22 MB)

      
              This report summarizes the research and development of a variable directivity Acoustic Warning Device (AWD) used as a locomotive horn. A Global Positioning System (GPS) was developed to control an arrangement of directional loudspeakers. Loudspeakers are arranged on the locomotive so that sound is directed forward when the horn is initially sounded 1/4 mile from a grade crossing. Other loudspeakers are sounded approaching a crossing to direct sound more to the wayside. This approach reduces wayside noise and maintains horn detectability. The work took place at the Transportation Technology Center (TTC) with wayside sound levels comparing well to predicted patterns.
      
            
      
      
              Last updated: Friday, February 11, 2022 U.S. DEPARTMENT OF TRANSPORTATION

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