Composite structures with desire mechanical properties can be tailored to embed microstrip antenna in aerospace systems
for reducing aerodynamic disturbance. The performance of a rectangular microstrip antenna in composite structures
is analyzed in spectral domain in this work. Analysis shows that the electromagnetics of antenna in spectral domain
is similar to the mechanics of composite structure in space domain. The electrical field, the immittance (impedance or
admittance), and the current density are equivalent to the stress, strain, and stiffness in mechanics of composite structures.
The governing equations, though may be of different dimensions, are also similar. It shall be expected that the performance
of a microstrip antenna on composite structures is different from that on isotropic structures; just as the
mechanics of the former is so different from that of the latter. Analysis confirms that antenna performance depends on
the structure's electromagnetic properties; similar to the mechanics of composite structures depends on the laminate
layers’ ply angle and stacking sequence.