Effect of weather on performance of an 8mm radar

The signal strength of echoes from a target (at a range of 2¿ miles over a sea path) were recorded over a period of two years and subsequently analysed to give the probability of fades greater than certain values. At the same time the rain-intensity régime was examined using several types of rain recorder. The results are given in the form of graphs showing the average frequency per year that a fade of a certain minimum intensity is to be expected, and its minimum duration. Graphs also show the fraction of time that signal strengths and signal/clutter ratios were less than certain limiting values. Various aspects of the results which concern the design of 8 mm radar, and its use at sea, are discussed.