Design of Dual-Band 5G Millimeter-wave Fan-shaped Antenna Based on Characteristic Mode Analysis

A dual-band 5G millimeter-wave microstrip antenna is proposed based on characteristic mode analysis (CMA), which consists of a $2 \times 2$ fan-shaped patch array open circular slot. The CMA is used to discuss the characteristic of the antenna, and two resonant modes are optimized at the frequency of 28.0 GHz and 38.0 GHz. According to the characteristic current distribution, the selected mode is excited by using the substrate integrated waveguide (SIW) slot to achieve multi-mode resonance, thus obtaining dual-band characteristics. Simulated results show that the impedance bandwidths are 27.5-29.4 GHz and 36.2-40.2 GHz, with realized gains of 6.9 dBi and 5.6 dBi, respectively. The proposed dual-band antenna is suitable for application in 5G millimeter-wave (MMW) communications system.