RADIOCOMMUNICATION BY BACKSCATTER

Experiments on line-of-sight backscatter of h.f. radio waves put in evidence the high values of the backscattering coefficient, concerning the sea near the coastal boundaries, when the vertically polarized component of the radio wave is considered it was also shown that the power lines, the railways, and the metallic structures in general are very efficient backscatters, to be considered when the h.f. backscatter occurs from a highly developed country. Another series of experiments was performed, concerning the possibility to reduce the broadening and the multipath effects in the backscattered echoes, and to increase the bandwidth capability of a radiocommunication system by backscatter it was shown that the echo pattern strongly depends on the antenna vertical beamwidth, and that the ionospheric irregularities producing multipath effects are of the focusing type their occurrence notably increases with the latitude.