in this study, absorption of high frequency radio waves in the ionospheric plasma have beeninvestigated. the wave equation was obtained in terms of ionospheric parameters. the numerical values ofthe absorption have been calculated for 4 mhz, 4.5 mhz and 5 mhz waves. the necessary parameters forcalculation have been obtained using an international reference ionosphere (iri) model. the altitudina...

The results of field experiments carried out in 2007, 2008 in a north-east part of the Black sea in region of city Gelendzhik, are given. Experiments targeted the development of a bottom topography remote (radar and optical) diagnostics. Experimental area is characterized by abrupt depth dumping (fall 50 1250 m), and irregularity of a bank vault (numerous canyons). Such bottom topography in the...

A wide variety of radio propagation models for different wireless services that specifically address varying propagation environments and operating frequency bands are generally known (Pahlavan et al. 1995; Jakes 1974). A large number of propagation prediction models have been developed for various terrain irregularities, tunnels, urban streets and buildings, earth curvature, etc. (E. Vehicular...

A whistler wave is a very low frequency electromagnetic wave generated by lightning discharges. As the electromagnetic wave travels through the plasma environments of the ionosphere and magnetosphere, it undergoes dispersion of a several thousand kilohertz. Because the propagation velocity decreases with frequency, the lower frequency components of the wave arrive later than the higher frequenc...

The spectrum between 30 GHz and 300 GHz is referred to as the millimeter wave band because the wavelengths for these frequencies are about one to ten millimeters. Millimeter wave propagation has its own peculiarities. This paper reviews the characteristics of millimeter wave propagation, including free space propagation and the effects of various physical factors on propagation. It was created ...

The spectrum between 30 GHz and 300 GHz is referred to as the millimeter wave band because the wavelengths for these frequencies are about one to ten millimeters. Millimeter wave propagation has its own peculiarities. This paper reviews the characteristics of millimeter wave propagation, including free space propagation and the effects of various physical factors on propagation. It was created ...

The significant effect of waves on coastal and marine activities urges the precise identification of wave characteristics using field measurements, theoretical studies, physical modeling or numerical simulations. In order to study thoroughly the wave climate in the Caspian Sea, a wave modeling and hindcast project was performed by Iranian National Center for Oceanography. In this study, one of ...