Design of Wideband Microstrip Antenna Based on Characteristic Mode Analysis

In this paper, by analyzing the characteristic mode of the rectangular patch, and the way of slotting and loading branches on the patch is used to broaden the bandwidth by more expected modes and resonant frequency points. The second desired mode is introduced by slotting, and a dual-band microstrip antenna is obtained. By loading branches at different positions, the bandwidths at different modes are widened respectively, and a common aperture antenna is obtained by combining. By loading two pairs of branches on the same patch, a microstrip antenna with 35% relative bandwidth is realized.