A phenomenon that the radiated power may be enhanced when an antenna is surrounded by a finite plasma shell has been found in numerical and experimental studies. In this paper, a physical model was built to express the mechanism of the radiated enhancement. In this model, the plasma shell is treated as a parallel connection of a capacitance and a conductance whose parameters change with the system parameters (plasma density, collision frequency, and antenna frequency). So, the radiated enhancement can be explained by the resonance between the plasma shell and the infinite free space. Furthermore, the effects of system parameters on the radiated power are given and effects corresponding to mechanisms are performed based on the physical model.

1.
M.
Kim
,
M.
Keidar
, and
I. D.
Boyd
, “
Analysis of an electromagnetic mitigation scheme for reentry telemetry through plasma
,”
J. Spacecr. Rockets
45
(
6
),
1223
1229
(
2008
).
2.
C.
Lin
and
K. M.
Chen
, “
Improved radiation from a spherical antenna by overdose plasma coating
,”
IEEE Trans. Antennas and Propag.
17
(
5
),
675
678
(
1969
).
3.
D. D.
Morabito
, “
The spacecraft communications blackout problem encountered during passage or entry of planetary atmospheres
,”
IPN Progress Report No. 42-150
,
2002
.
4.
R. W.
Ziolkowski
and
A.
Erentok
, “
Metamaterial-based efficient electrically small antennas
,”
IEEE Trans. Antennas Propag.
54
(
7
),
2113
2130
(
2006
).
5.
A. M.
Messiaen
and
P. E.
Vandenplas
,
Electron. Lett.
3
,
26
(
1967
).
6.
T. I.
Bichutskaya
and
G. I.
Makarov
, “
Radiation from an electric dipole surrounded by a plasma cylinder with a cavity
,”
Radiophys. Quantum Electron.
45
(
7
),
509
519
(
2002
).
7.
C. C.
Lin
and
K. M.
Chen
, “
Radiation from a spherical antenna covered by a layer of lossy hot plasma: Theory and experiment
,”
Proc. Inst. Electr. Eng.
118
(
1
),
36
42
(
1971
).
8.
H. R.
Stuart
and
A.
Pidwerbetsky
, “
Electrically small antenna elements using negative permittivity resonators
,”
IEEE Trans. Antennas Propag.
54
(
6
),
1644
1653
(
2006
).
9.
W.
Rotman
, “
Plasma simulation by artificial dielectrics and parallel-plate media
,”
IRE Trans. Antennas Propag.
10
(
1
),
82
95
(
1962
).
10.
J. A.
Stratton
,
Electromagnetic Theory
(
John Wiley & Sons
,
2007
).
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