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The results of microwave measurements for some objects combining multifrequency measurements and transversal scanning is presented. Longitudinal distance dependencies of reflectivity have been obtained by synthesis from multifrequency data. The multifrequency measurements and synthesis have been done in real-time. The measurements in free space were carried out by the apparatus using measuring modules of scalar reflectometer of series Р2 (R2). The combination of data in longitudinal and transversal directions produced radio images of some dielectric structures.

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The accurate measurement of radiation patterns of electrically small antennas (ESAs) requires a reflectionless environment and minimal disturbance from the antenna support and feed cable. These influence factors constitute the "antennato-range interface" and hence the deviation of the antenna performance from an ideal non-invasive set-up. A study was carried out at the UK National Physical Laboratory of disturbance minimisation in the measurement of radiation patterns of ESAs. To eliminate the large distortion associated with the unwanted radiation from a coaxial cable an electrooptical (EO) transducer was employed. The shielding effect of different transducer designs is assessed with an electrically small ultra-wide band antenna (UWB). Numerical results for the radiation pattern of a dielectric resonator ESA operating at 2.45 GHz are compared with the measured results using an EO transducer or a cable.