Target and clutter observations with an improved 10 ns Ka-band radar

An improved version of a portable, microprocessor controlled monostatic 10 ns instrumentation radar is described together with new illustrative results. Measured calibration target fluctuation is less than 0.4 dB peak-to-peak for 5 second record lengths. This figure combined with the good ability of avoiding confusing multipath phenomena opens up new possibilities for RCS and clutter experiments. Observed mean reflectivity of deciduous forest is -5 dB(m²/m²) with perpendicular illumination and the ground clutter level for 0.5 degree grazing angle and lightly cultivated soil is typically -12 dB(m²/m²). Studies of volumetric clutter reveal the fine structure of rain and are in line with previously measured statistical reflectivity levels including a limit of -24 dB(m²/m³) for 80 percent cumulative probability in 10 mm/hr rain.