Design and modeling of communications system for interoperable positive train control

Positive train control (PTC) provides a critical safety backup for train operations to protect against the consequences of human error. With the Rail Safety Improvement Act of 2008 mandating positive train control for most North American railroads, railroad community efforts are underway to develop an interoperable PTC communications system over a 220 MHz network. A robust, reliable, and interoperable communications system is one the most vital components to the success of the PTC technology. This paper presents the design and modeling of a 220 MHz interoperable PTC system. The paper introduces a communication protocol that is designed to efficiently meet PTC communications needs within the available 220 MHz spectrum. The paper also presents simulation system architecture for analyzing the performance of the 220 MHz PTC system. Extensive simulations are conducted to evaluate the system performance and validate the design.