Radio wave propagation, ionosphere

Atmospheric plasma research was originally stimulated by the interest in radio wave propagation and therefore was focussed on the ionosphere. Thus, the early in situ ion composition measurements were made in the ionosphere at altitudes above about 100 km using rocket-borne spectrometers [15, 16, 17]. Below 100 km, the atmospheric gas pressure becomes so large that mass spectrometers have to be pumped which represents a major barrier for extending in situ ion composition measurements downwards into the mesosphere. Such measurements became technically feasible only with the advent of compact high speed cryopumps which could be used on rockets. 

The study of the ionosphere has largely been performed by observation of the properties of radio wave propagation through this medium. In this work we will not attempt to present an exhaustive study of the interaction of electromagnetic waves and a weakly ionized plasma, nor... 

Potemra, T.A., Ionizing radiation affecting the lower ionosphere, in ELF-VLF Radio Wave Propagation. Holtet, J.A. (ed.), Reidel Publishing, Dordrecht, The Netherlands, 21, 1974. 

Aarons, J., ed. 1984. Ionospheric radio wave propagation. Handbook of Geophysics and Space Environments, Chap. 10,1983 Revision. Environmental Research Paper 879. Air Force Geophys. Lab, HanscomAFB, MA. 

Al pert, Y.L., 1974. Radio Wave Propagation and the Ionosphere. Consultants Bureau, Plenum, New York. 

Hyperlinks Clickable pointers to online content in Web pages other than the page one is reading. Internet Service Provider (ISP) Organization that provides access to the Internet for a fee. Ionosphere Part of the upper atmosphere that is ionized because of radiation from the sun, and therefore it affects the propagation of the radio waves within the electromagnetic spectrum. Kilobit Quantity equal to 1,000 bits. 

The representation of the radio wave path in Fig. 13.29 and the previous discussion have only considered a direct path between the receiver and transmitter. In reality, there are two major modes of propagation the skywave and the groundwave. The skywave refers to propagation via the ionosphere, which consists of several layers of ionized particles in the Earth s atmosphere from approximately 50 to several hundred kilometers in altitude. Some frequencies will be reflected by the ionosphere resulting in potentially longdistance propagation. This propagation mode is discussed in detail in a later section. 

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