Plasma diagnostics of the solar corona using decimetric radio waves (review)

The solar corona is a very dynamic plasma on time scales down to a few tens of microseconds. The various emissions at decimetric wavelength are briefly reviewed. Several of them seem to be caused by energetic (non-thermal) electrons accelerated in flares or flare-like processes releasing free magnetic energy. The use of decimetric radiation as diagnostics of the acceleration process, the ambient plasma, and the non-thermal particles requires a solid understanding of the emission process. Although we are still far from this in most cases, some information can already be derived from the observations.Institute of Astronomy, Federal Institute of Technology (ETH), Zurich, Switzerland. Published in Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 37, No. 7, pp. 809–820, July, 1994.     

Multiple scattering of HF radio waves propagating across the sea surface

A problem that is of considerable importance to the HF communications and radar communities is the calculation of the spatio-temporal modulations imposed on a radio wave as a result of propagating across a rough sea surface. We derive equations, in the form of a multiple-scattering series, describing the spatio-temporal structure of a radio wave at a point on the rough sea surface after propagation from an antenna at another point on the surface. We present calculations illustrating the sensitivity of the resultant Doppler spectra to ocean surface conditions, as described by well known parametric models. The generality of the approach means that it can easily accommodate user-specified antenna patterns, arbitrary coastline geometries, arbitrary sea-wave spectrum models, wave-field inhomogeneity and a wide range of seawater conductivities.     

Spatial spectrum of a radar signal in glancing propagation above the sea surface

Pacific Oceanographic Institute, Far-East Branch of the Academy of Sciences of the USSR. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 34, No. 3, pp. 325–327, March, 1991.     

应用非线性薛定谔方程模拟深海内波的传播

本文选取东沙岛以东深海区域,应用描述深海内波的非线性薛定谔方程,采用啁啾的思想,研究了频散和非线性效应之间的关系,模拟了深海内波的传播.数值模拟内波演变趋势与MODIS影像拍摄到的内波演变趋势基本符合,从而验证了应用非线性薛定谔方程模拟深海弱非线性内波传播的合理性. 关键词： 深海内波 啁啾 非线性薛定谔方程 频散和非线性