In dielectric spectroscopy, an analysis is made of the function of the complex permeability
[[epsilon].sup.*] of insulation by the frequency and voltage range [5-7]:
The reflection loss (RL) of composite nanofibers was calculated by Matlab based on the relatively complex permeability
and permittivity at a given frequency and matching thickness according to the following equations:
With respect to dynamic magnetic properties, we calculated the frequency- dependent complex permeability
for the Zn-Co-Ni ferrite film using Eq.
([mu]' and [mu]") was calculated from [B.sub.m] cos [delta]/([[mu].sub.0][H.sub.m]) and [B.sub.m] sin [delta]/([[mu].sub.0][H.sub.m]), respectively, where [delta] is phase difference and can be obtained directly from the computer measurement and control system.
The value of imaginary part ('') of complex permeability
decreases after Sm3+ substitution while no change observed in real part (') of complex permeability
with Sm3+ substitution for all samples which has been discussed using electromagnetic theory.
Lossy magnetic wires are characterized by a complex permeability
[[mu].sub.m] and complex permittivity [[epsilon].sub.m].
Conventional spinel type ferrites do not function well in the GHz range due to a drop in the complex permeability
([[mu].sub.r]) as given by Snoek's limit .
Application of materials in the microwave, aerospace, and communications demands an accurate knowledge of material properties such as complex permittivity and complex permeability
. The active research fields like materials science and electrical and electronic engineering  need necessarily information about permittivity and permeability for developing novel microwave materials.
The properties of a material may be specified by two complex constants called complex permittivity ([epsilon]) or dielectric constant and complex permeability
Szendrenyi, et al., "An Alternative Broadband Method for Automatic Measurement of the Complex Permeability
and Permittivity of Materials at Microwave Frequencies," IEEE MTT-S Symp.
Hatakeyama, "Frequency dispersion and temperature variation of complex permeability
of Ni-Zn ferrite composite materials," J.
Varadan, "A free-space measurement of complex permittivity and complex permeability
of magnetic materials at microwave frequencies," IEEE Trans.