Proceedings with Extended Abstracts (single PDF file) - Radio ...

Fig. 11 Plots of temporal variations of target locations in the horizontal plane(upper circles, which represent about the beam width) and the positions in vertical(z) and horizontal (x) and (y) planes; the color codes indicate negative/positivedr/dt and amplitudes as function of zenith angle, deduced over a period of 30seconds. In the lower part the spectra are shown, which correspond to the otherdisplays above. The vertical scale corresponds to the range resolution of 300 mand the x, and y-scales are determined by the antenna beamwidth.>10 dB0.5 m/saway0 dB0.5 m/stowardsFig. 12 A 30-sec average projection of power and radial velocity of a signal fromone range gate at 6.3 km height into the horizontal plane measured with the MUradar with the SDI-FDI combination, applying a Fresnel zone filter. The centre isthe vertical direction and the outer scales are determined by the beamwidth(±200m at 6 km height). The upper right-hand corner are NE etc.In Fig. 11 data of this kind are presented in polar plots (upper panels). The left-hand oneshows that dr/dt (i.e. changes in position of the mean scattering center) are depending onazimuth. Also the maximum signal amplitude is close to the vertical direction. The lower lefthandpanels show that the scattering centers are located all over the range gate, and the lowerright-hand panel shows that they are mostly confined to a part of the range gate (about onethird of the range gate width of 300 m). The former is an indication of a “wide layer” and thelatter indicates a “thin layer”, which we also call sheet or lamina. Comparing this thin layerand the instantaneous radial velocities measured by this technique with the correspondingDoppler spectra shown in that graph, it is noticed that negative velocities come from one sideof the vertical and positive from the other side. This is an indication that the width of the455