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E F
1
PF
1
PF
R F
R F
k 2
2
k 2
2
B 1
B 1
R 0
R 0
R 0
R 0
0
0
E
E
1
PE
R E s
I uE
PE
V uE
( a )
( c )
E F
1
PF
1
PF
R F
R F
V uF
k 2
2
B 1
k 2
2
B 1
R 0
R 0
R 0
R 0
0
0
1
PE
R E s
V uE
1
PE
R E s
I uE
E E
( b )
( d )
Figure 6.41 Circuit models for E-F coupling. (a) Mapping of an electric field from an
E s layer to the F layer. (b) Wind driven E s layer source. (c) Thévenin equivalent for (b).
(d) Wind-driven sources in both E s and F layers.
conductivity of the F region (
PF ), and the FLI Pedersen conductivity of the E s
layer (
PE ) as shown. It is assumed that the source has a sinusoidal form with
wavenumber k . Figure 6.41a shows how the electric field in the F layer due to
an electric field applied in the E s layer is given by a voltage divider between
the field-aligned resistor R 0 and the F-layer resistor R F . Figure 6.41b shows
the voltage divider applicable to determining the F- and E s -layer electric fields
due to a wind-driven Hall current, such as in the wind-driven Haldoupis et al.
(1996) polarization mechanism. Figure 6.41c shows the Thevenin equivalent of
Fig. 6.41b, and Fig. 6.41d shows the generalization to sources in both the E s and
F layers.
Using Fig. 6.41d, Cosgrove and Tsunoda (2004b) derive the following approx-
imate expression for the coupled system growth rate in term of the isolated
 
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