“…In the past years, a large number of publications have been dedicated to better understanding this relationship and applying it to rice detection and rice monitoring (Le Toan et al, 1997, Inoue et al, 2002, Suga and Konishi, 2008, and Bouvet et al, 2009). In summary, these studies have shown that lower frequencies (L-and Cband) penetrate deeper into the rice plant than higher frequencies, while only higher frequencies (X-band) interact with grain water content and grain weight sufficiently to show a dual-peak signal in σ° during the rice season (Inoue et al, 2002, Suga and Konishi, 2008, Oh et al, 2009and Kim et al, 2009. Further, short wavelengths (X-, Ka-, Ku-band), especially at large incident angles, are sensitive enough to detect even very small rice seedlings just after transplanting.…”