The conventional series-fed endfire dipole antenna has a wide impedance bandwidth and is inexpensive to manufacture. However, it has a disadvantage: its size is large because of the large inter-dipole spacing, which is required to satisfy the endfire condition for good antenna radiation characteristics. Here, we propose a two-dipole endfire antenna with a reduced size. The miniaturized endfire antenna was designed using a meander line to reduce the interdipole spacing while ensuring that the endfire condition was satisfied. Furthermore, the overall width of the antenna was reduced using a bent dipole and a corrugated ground plane. The electrical size of the proposed antenna was only 0.33λ0 x 0.33λ0 x 0.014λ0 at a center frequency of 5 GHz, its –10 dB impedance bandwidth was 4.47–5.72 GHz (24.5%), and the gain at the center frequency was 5.9 dBi.
This work was supported in part by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. NRF-2022R1F1A106 5324); in part by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2021R1A4A1030775); and in part by Institute of Information & communications Technology Planning & Evaluation (IITP) grant funded by the Korea government (MSIT) (No. 2022-0-00704-001, Development of 3D-NET Core Technology for High-Mobility Vehicular Service).
