Radiation pattern reshaping designs for slot antenna based on the third-order mode

Abstract

Based on radiation pattern reshaping technology, two slot antennas (SAs) operating on the third-order mode are designed. Both of them obtain high-gain characteristic and stable bidirectional radiation. The radiation characteristic of the SA three-order mode is analyzed. Then, the influence of the finite ground edge’s diffraction on radiation pattern of SA is considered. By using the finite ground with a suitable size, the main lobe in radiation direction can be effectively regulated. On this basis, according to the equivalent magnetic current distribution in slot, this paper proposes two radiation pattern reshaping design schemes (a. Folding rectangular slot; b. Loading C-shaped slots). Both design schemes can suppress the side lobes and regulate the main lobe in the radiation pattern. Two proposed SAs can achieve stable bidirectional radiation and obtain high-gain response. Finally, two SAs are fabricated and measured. The measured results show that two SAs achieve bidirectional radiation. The peak gains of two SAs are 6.88 dBi and 7.51 dBi, respectively.