Raw Observation Data, in Real Time. The role of a reference station in an RTN is to be quite stable, to collect good quality raw observations and to transmit these to the Central Processing Center (CPC) in real-time. As discussed in the previous installments of this series, the fundamental design of an RTN consists of several key components, all of equal importance: a network of reference stations meeting rigorous metrics with respects to positional integrity and data quality, a central processing center to gather the data and produce correctors, and real-time communications