Study Of Radio Wave Propagation Research Articles

Observations on the U.S.S.R. Earth satellites and the study of radio-wave propagation

Measurements of bearing, angle of elevation and Doppler frequency shift have been performed at Slough on transmissions from the Russian Earth satellites. The examples considered here indicate that the observed phenomena can be accounted for satisfactorily in terms of our present knowledge of ionospheric propagation. A short section is included on orbital determination from the measurements.

The diffraction of waves in passing through an irregular refracting medium

A relation is derived between the angular power spectrum of waves emerging from a thin diffracting screen random in two dimensions and the auto-correlation function describing the irregularities of the field as it emerges from the diffracting screen. The special case of an isotropic screen characterized by an auto-correlation function which depends only on distance and not on direction is discussed for normal and oblique incidence. Multiple scattering of waves caused by volume irregularities of the dielectric constant is considered. The angular power spectrum and the auto-correlation function describing the irregularities of the diffraction field caused by multiple scattering in a thick slab are determined. The results are compared with those obtained by Hewish for a thin phase-changing screen. The results are discussed in terms of problems arising in the study of radio-wave propagation.

Survey of Radio Noise

IT has long been appreciated that satisfactory radio communication depends upon the establishment at the receiving station of a minimum strength of signal above the prevailing noise. During the War, it became clear that the study of atmospheric noise-level and the limitation which it imposes on signal reception has received far less attention in recent years than the study of radio wave propagation. In 1943, the Radio Research Board, in co-operation with British inter-Service organisations, considered that it was desirable to supplement our existing knowledge of the nature, origin and prevalence of atmospherics, with particular reference to their effect on radio reception in various parts of the world. It was recognized that this would involve the carrying out of a long-term programme of research in order to place our knowledge on a satisfactory basis in relation to other advances in radio reception technique. Before embarking upon such long-term research, the Board recommended that a survey of existing knowledge in this field should be made as soon as possible; and it is in consequence of this recommendation that Radio Research Special Report No. 15, entitled "Survey of Existing Information and Data on Radio Noise over the Frequency Range 1-30 Mc./s.", has recently been published by the Department of Scientific and Industrial Research (London: H.M. Stationery Office. 3s. net).