B. L. Nie, P. G. Du
Copyright © 2013 SciRes. OJAppS
50
Table 2. Resonance points of the enclosure with inner exci-
tation.
Modes Frequency (GHz)
101
y
TM 0.89
TEM 1.08
cavity-slot 1.12
slot 1.23
111
y
TM 1.37
201
y
TM 1.43
cavity-slot 1.53
Table 3. Resonance points of the enclosure with outer -
polarized plane wave excitation.
Y
Modes Frequency (GHz)
101
y
TM 0.84
cavity-slot 1.16
slot 1.25
cavity-slot 1.40
012
y
TE 1.47
Table 4. Resonance points of the enclosure with outer -
polarized plane wave excitation.
Z
Modes Frequency (GHz)
101
y
TM 0.84
cavity-slot 1.16
102
y
TM 1.21
110
y
TE 1.27
cavity-slot 1.40
012
y
TE 1.47
resonance is absent when the excitation source is
Z-polarized plane wave. But the two resonance points
associated with coupling of cavity and slot exist. More-
over, TMy102 mode and TEy110 mode are excited.
4. Conclusions
In this paper, the FEM is employed to investigate the
shielding properties of slotted enclosure with outer or
inner excitation. The resonance phenomena of slotted
enclosure are studied in detail for both inner and outer
excitations. Different polarization configurations of inci-
dent plane wave for the outer excitation case are also
investigated, especially for their resonance behavior. It
also shows that the same enclosure can have very differ-
ent resonance behavior when it is excited by different
sources, Which could be helpful for shielding enclosure
design.
5. Acknowledgements
The authors thank the National Natural Science Founda-
tion of China (Grant No. 51175068), the China Scholar-
ship Council (CSC), and the Fundamental Research
Funds for the Central Universities of China for their
supporting.
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