Fall estimation of microstrip antenna array side lobe levels by using cosine-type distribution

Cosine-type microstrip feeding structure, has been modeled, designed and fabricated for array with 16-radiating elements. Analytical data show good agreement with experimental results of considered structure fabricated on RT-Duroid substrate material with thickness h=1.27 mm and electric permittivity ε_r=10.2 for midband frequency around 1 GHz. Cosine distribution possesses the widest realizable dynamic amplitude range of excitation coefficients, which makes it more eligible to estimate side lobe levels fall of the feeding structure for other tapered distributions. This approach is applied before the fabrication process in which it is considered to be as time and money saving strategy.