Fig. 6
The average of absolute values of transmission and reflection coefficients versus the incident frequency at different averages of permittivity of dielectric slabs \(\:{\varepsilon\:}_{av}=3.5,\:3.0\:and\:2.5\). Figure (a–d) correspond to \(\:\left|{f}_{1,final}\right|,\:\left|{f}_{2,final}\right|,\:\left|{b}_{1,final}\right|\:and\:\left|{b}_{2,final}\right|\), respectively.