MHD-Wave Generation by HF-Heating - Hydromagnetic Waves in the Magnetosphere and the Ionosphere - page 374

10 2 MW. The amplitudes of the man-made magnetic vari-
ations at modulation period

nighttime for W 0 ≈

10 s can reach the magnitude of the natural 10 s
pulsations. These values are correct only under the center of the generated
inhomogeneity. Near the inhomogeneity, the magnetic field decreases approx-
imately as r − 1 ( r is the distance to the center of the inhomogeneity) and as
r − 2 far from it. An increase in the antenna gain at a given transmitter power
leads to a decrease in the magnitude of the variations generated, as follows
from the magnetic field estimates obtained.
These currents produce also an MHD-wave going to the magnetosphere
to the conjugate ionosphere. Estimates of the emitted Alfven wave caused by
such oscillated ionospheric current will be given in the next chapter.

≈

References

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