Reflection Characteristics of Layered Media in Polar Mesopause Related to Polar Mesosphere Summer Ec

来源 :Plasma Science and Technology | 被引量 : 0次 | 上传用户:leezhenghui
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Polar mesosphere summer echoes (PMSE) are very strong radar echoes from altitudesclose to the polar summer mesopause. The data from sounding rocket campaigns indicatethat the radar signal to noise ratio (SNR), electron density and dust charge density of polar mesospherein summer show obvious layered structure. In this paper the theory of wave propagationin layered media is used to study the reflectance and SNR at each layer in polar mesosphere. Thecalculated SNR using theory of dusty plasma is found in good agreement with the experimentalresult, which may imply that the intensity of the radar echoes reflected by the layered structure inpolar mesosphere where polar mesosphere summer echoes used to occur can interpret partially thephenomenon of PMSE. In other words, reflection may play an important role in the occurrence ofPMSE. Polar mesosphere summer echoes (PMSE) are very strong radar echoes from altitudesclose to the polar summer mesopause. The data from sounding rocket campaigns indicate the the radar signal to noise ratio (SNR), electron density and dust charge density of polar mesospherein summer show obvious layered structure. In this paper the theory of wave propagation in layered media is used to study the reflectance and SNR at each layer in polar mesosphere. Thecalculated SNR using theory of dusty plasma is found in good agreement with the experimental result, which may imply that the intensity of the radar echoes reflected by the layered structure inpolar mesosphere where polar mesosphere summer echoes used to occur can interpret partially the phenomenon of PMSE.
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