  There is a huge demand to accurately determine the magneto-electrical
properties of particles in the nano sized regime due to the modern IC
technology revolution and biomedical application science. In this paper, we
present a microwave waveguide measurement technique for complex permeability
and permittivity of expensive nano sized magnetic powder materials. In the
measurement process, Agilents 8510C vector network analyzer was used to have a
standard TRL calibration for free space inside the waveguides. In order to
maintain the recommended insertion phase range, a very thin prepared sample was
loaded inside the calibrated waveguide. Also, the loaded materials magnetic and
dielectric effects were considered into the cutoff wavelength of the
propagation constant of the TE10 wave from the geometrical dimensions of the
waveguides. This makes the measured permeability and permittivity more reliable
than commonly used techniques. The six different compounds of nano sized
ferrite powders (Fe3O4, CuFe2O4, CuFe2O4Zn, Fe2NiO3Zn, BaFe12O19, and
SrFe12O19), in which the average diameter of nano particles is less than 40nm
were purchased from Sigma-Aldrich, Inc for measurement purposes employing this
technique. For industrial benefits, we present the complex permeability and
permittivity on the frequency range from 3.95GHz to 5.85GHz. The measured
results showed that the dielectric permittivity of these materials is quite
different from those of solid state materials. Index Terms, Nano ferrites,
waveguide technique, permeability, permittivity.
