IEC 61338-1-4:2005-11(en-fr) describes the measurement method of dielectric properties for dielectric resonator materials at millimetre-wave frequency. This standard consists of two measurement methods: a) the dielectric rod resonator method excited by NRD-guide (Non-Radiative Dielectric waveguide) and b) the cut-off waveguide method excited by coaxial cables with small loops.