https://www.mdpi.com/1424-8220/20/21/6328
A New Planar Microwave Sensor for Building Materials Complex Permittivity Characterization
A new microwave sensor is proposed to characterize the complex relative permittivity of building non-magnetic materials and used in the characterization of...
a newmicrowave sensorbuilding materialscomplex permittivityplanar
https://www.nist.gov/publications/complex-permittivity-beryllium-oxide-between-100-and-300kelvins-93-gigahertz
Complex Permittivity of Beryllium Oxide Between 100 and 300Kelvins at 9.3 Gigahertz | NIST