The Effect of Laminate Angles in Composite Substrates on the Performance of Rectangular Microstrip Antenna

The performance of a microstrip antenna has been known sensitive to substrate’s dielectric properties, which is dependent on the angle of laminate layers inside a composite laminated substrate. Modal analysis in spectral domain is applied to investigate the resonant frequency and radiation pattern of rectangular microstrip antenna on composite substrates. It is shown that the substrate’s dielectric properties are dependent upon the laminate angles, i.e., upon the orientation of the antenna relative to the substrate’s fiber direction. For the same operating frequency, the antenna size on composite substrates is larger than that on isotropic substrates, and the far field pattern is also more directional.