Amplitude Statistics of Nakagami‐m Distributed Weather Clutter Observed by X‐Band Marine Radar

Abstract

Under strong wind caused by a low pressure with fronts passing near Honshu, I have observed weather clutter containing targets (ships) using an X‐band marine radar with a frequency of 9.41 GHz, a beamwidth of 1.0°, a pulsewidth of 0.5 μs, and a pulse‐repetition frequency of 1600 Hz. To investigate such clutter amplitude statistics, I have introduced the Nakagami‐m distribution to radar signal processing for the first time and used the Akaike Information Criterion (AIC). It has been found that the weather clutter amplitudes obey the Nakagami‐m distribution with the shape parameter of m = 5.85 for entire data and the log‐normal, Weibull, log‐Weibull, and Nakagami‐m distributions with the shape parameters of σ = 0.189 to 0.259, c = 6.52 to 7.81, c = 26.66 to 35.51, and m = 5.23, respectively, for small data within the beam width of an antenna. The number of the minimum AIC (MAIC) of the log‐normal, Weibull, log‐Weibull, and Nakagami‐m distributions to data is 4, 12, 4, and 1, respectively, from 21 small data. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.