A durable laboratory apparatus for the measurement of soil dielectric properties

A coaxial transmission/reflection measurement system is described which has been used to collect complex dielectric property data for soils. Measurement variables include frequency (45 MHz-26.5 GHz), sample temperature, moisture content, and sample density (the last two accurately determined through mass and volume measurements). The system is shown to adequately measure the properties of pure water and air. Representative soil data are also shown for a clean sand and a very wet clay.