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Centralized Interlocking (CIXL) for Moving Block Research Project

Document Series
Research Results
Federal Railroad Administration
Report Number
RR 21-07
Subject Positive Train Control
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

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