A microstrip-fed antenna is disclosed having a first dielectric substrate and a second dielectric substrate. The second dielectric substrate is disposed on the first dielectric substrate and the first dielectric substrate has a relative permittivity greater than or equal to the second dielectric substrate. The antenna further includes a microstrip line formed in the second dielectric substrate and a metal layer formed in the second dielectric substrate. The metal layer is positioned between the microstrip line and the first dielectric substrate and includes a slot.