On the Radiation Properties of the Complementary Strip-Slot Element

The complementary strip-slot radiating element is a microstrip-fed slot modified by introducing its complementary stub on the layer of the microstrip. Previous works have shown that the introduction of the stub into the conventional slot results in an ultra broad impedance bandwidth and have provided a lattice-network equivalent circuit for its precise modeling. In this contribution, an interesting property of the symmetric lattice networks is highlighted and used to illustrate why the complementary strip-slot radiates as the conventional microstrip-fed slot, thus corroborating the conclusions of previous works based on empirical results.