Radio Spectrum for PTC Applications

The wireless communications link is both a major and critical component of recently introduced PTC systems such as ACSES and I-ETMS. With PTC systems rapidly moving from optional to required, each agency planning on deploying a PTC system needs to properly secure wireless spectrum for its PTC operation. The RF spectrum in the U.S. is a scarce resource, availability and demand of which were not addressed by the U.S. Congress’ RSIA-2008; therefore, each railroad has to obtain sufficient spectrum for its PTC system as an individual party. There are certain key questions that must be answered during the spectrum acquisition process: What licenses are available and who are the potential sellers? Are there any interference or other ownership issues? How much does the desired spectrum cost? These and other questions must be considered as part of the Positive Train Control system’s design and deployment. This paper identifies spectrum parameters and options that must be considered as part of the successful deployment of wireless train control applications.