A substrate design that uses a ferrite ring to enhance the gain of a microstrip patch antenna without compromising the bandwidth is proposed. This design forces constructive interference between the incident and reflected fields inside the substrate. The interference is created by introducing a ferrite ring at a distance d1 from the circumference of the patch with a ring width d2. Initial values of d1 and d 2 of one-quarter of the free-space wavelength (d1 = d 2 = λ0/4) are selected. An unbiased ferrite, with relative permeability of μr2 = 14, relative permittivity of r 2 = 10, dielectric loss tangent tan δ e= 0.0017, and magnetic loss tangent tan δ m= 0.0391, is used. Using HFSS, the results of the patch antenna above a conventional substrate (i.e., no ferrite ring) and above the hybrid substrate (which includes the ferrite ring) are compared. Enhancements of about 4 dB in gain and nearly 1% in impedance bandwidth are obtained by using the hybrid substrate instead of the conventional one.
- Antenna gain
- microstrip antennas
ASJC Scopus subject areas
- Electrical and Electronic Engineering