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            Centralized Interlocking (CIXL) for Moving Block Research Project
      

      
  Document Series
              Research Results


      
  Author
          Federal Railroad Administration


      
Report Number
              RR 21-07

  Office
              RDI-23


      Subject
                    Positive Train Control


      
  Keywords
              Centralized interlocking system, CIXL, Quasi-Moving Block, QMB, Positive Train Control, PTC, Communications-Based Train Control, CBTC, control point, CP, Wayside Status Messages, WSM, railroad, train control


      

      
      
              
                  
      
              
  Document
              CIXL Moving Block Research.pdf (463.86 KB)

      
              From September 9, 2019, to March 8, 2021, the Federal Railroad Administration (FRA) sponsored Transportation Technology Center, Inc. (TTCI), to develop and analyze a concept for a centralized interlocking (CIXL) system that supports moving block methods of train control, improves overall availability and maintainability, and satisfies the needs of North American railroads.
      
            
      
      
              Last updated: Tuesday, April 27, 2021 U.S. DEPARTMENT OF TRANSPORTATION

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