ABSTRACT
The previous two chapters have been concerned
with obtaining directional information for the
purposes of airborne navigation. In this chapter
we will look at a system that provides the crew
with the distance to a navigation aid. Distance
measuring equipment (DME) is a short/medium-
range navigation system, often used in
conjunction with the VOR system to provide
accurate navigation fixes. The system is based on
secondary radar principles, and operates in the L-
band of radar. Before looking at what the system
does and how it operates in detail, we need to
take at look at some basic radar principles.
