A U-shaped wide-slot dual-band broadband NB-IoT antenna with a rectangular tuning stub

In order to meet the requirements of NB-IoT dualband and broadband communication, a U-shaped wide-slot dualband broadband NB-IoT antenna with a rectangular tuning stub is proposed. The proposed antenna has a wide rectangular tuning stub, which excites two different operating modes, thus forming the dual-band characteristics of the antenna. The U-shaped wide slot is used on the ground plate of the antenna to form electromagnetic coupling and realize the broadband characteristics of the antenna. The simulation results show that the impedance bandwidth (RL<; -10dB) of the antenna are 0.80 GHz~2.88 GHz (relative bandwidth is 97.7%) and 3.96 GHz~6.35 GHz (relative bandwidth is 43.5%). It covers the NB-IoT communication band, expands the WLAN and Bluetooth bands, and achieves the dual-band broadband characteristics of the NBIoT antenna.