We observed ground clutter from cultivated land in a range interval 31.9 to 37.5 nmi (59.1 to 69.5 km), over an azimuth interval of 90.57° to 113.43°, using an L-band long-range air-route surveillance radar (ARSR) having a frequency 1.33 GHz, a beamwidth 1.23°, a pulsewidth 3.0 μs. Weather conditions were clear and the wind velocity was 2 to 10 knots (1.0 to 5.1 m/s). Recorded data has been processed by single and double canceller moving target indicator (MTI) processors. To determine the amplitude statistics of ground clutter after single and double canceller MTI processing, we introduced the Akaike Information Criterion (AIC), which is more rigorous fit of the distribution to the data than the least squares method. We have found that the ground clutter after single canceller MTI obeys the log-Weibull distribution with the shape parameter of c=6.55 for entire data, and the Weibull, log-Weibull and K-distributions with the shape parameters of 1.79 ≤ c ≤ 1.95, 7.27 ≤ c ≤ 7.45 and 5.53 ≤ ν ≤ 20.39, respectively, for data within the beam width of an antenna. And the ground clutter after double canceller MTI obeys the K-distribution with the shape parameter of ν=4.00 for entire data, and the Weibull and K-distributions with shape parameters of 1.67 ≤ c ≤ 1.94 and 3.18 ≤ ν ≤ 25.75, respectively, for data within the beam width of an antenna.