Table 3.1 Parameters of the flat cross dipole element FSS. Parameter Value(mm) Description m 20 Size of unit cell g 1 Gap between copper and unit cell L 18 Length of copper w 1 Width of copper t 0.1 Thickness of copper n 1 Thickness of substrate Simulation results: Figure 3.2 Transmission and reflection response of flat cross FSS array. Figure 3.2 shows the transmission and reflection response of the flat cross FSS array. The resonant frequency of the structure is 7.92GHz. Clearly, it is a band-stop filter that will reflect the incident signals at 7.92GHz. The fractional bandwidth can be calculated as the frequency difference at -10dB divided by the resonant frequency, which is approximately equal to 9.67%. The transmission response of the flat FSS for several incident angles is shown in Figure 3.3. Both TE and TM modes are considered. As it can be seen, the resonant frequency decreases with the increase of the incident angle for TE mode. On the other hand, the resonant frequency increases as the incident angle increases for TM mode. In addition, the frequency shift of TE and TM modes vary within 0.83GHz and 0.25GHz, respectively. Therefore, TM mode is more stable than TE mode. (a) TE mode
Table 3.1 Parameters of the flat cross dipole element FSS. Parameter Value(mm) Description m 20 Size of unit cell g 1 Gap between copper and unit cell L 18 Length of copper w 1 Width of copper t 0.1 Thickness of copper n 1 Thickness of substrate Simulation results: Figure 3.2 Transmission and reflection response of flat cross FSS array. Figure 3.2 shows the transmission and reflection response of the flat cross FSS array. The resonant frequency of the structure is 7.92GHz. Clearly, it is a band-stop filter that will reflect the incident signals at 7.92GHz. The fractional bandwidth can be calculated as the frequency difference at -10dB divided by the resonant frequency, which is approximately equal to 9.67%. The transmission response of the flat FSS for several incident angles is shown in Figure 3.3. Both TE and TM modes are considered. As it can be seen, the resonant frequency decreases with the increase of the incident angle for TE mode. On the other hand, the resonant frequency increases as the incident angle increases for TM mode. In addition, the frequency shift of TE and TM modes vary within 0.83GHz and 0.25GHz, respectively. Therefore, TM mode is more stable than TE mode. (a) TE mode
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