A 1-D Tightly Coupled Dipole Array for Broadband mmWave Communication

A wideband phased array antenna for the use in 5G millimeter-wave (mmWave) mobile terminal is presented. The proposed array antenna was designed based on the tightly coupled dipole array (TCDA) technique to achieve a low profile and broadband impedance matching characteristic. Unlike the previously reported TCDAs implemented with 2D arrays on a vertical ground plane, the proposed 1D array antenna exhibited the maximum beam direction parallel to the ground, which is suitable for mobile terminal applications. Using a full-wave electromagnetic simulation tool, a
$1\times8$
TCDA was designed on a multilayer substrate including a reflector surface in the middle to replace a vertical ground plane. Prototypes were fabricated and measured with feeding networks designed for 0° and 30° scanning scenarios. The size of the proposed antenna (excluding the feeding network) was
$42.3\times 12.05\times0.535$
mm
³
. The measured bandwidth that subjects to S
₁₁
< −10 dB criterion was 22.5–32.5 GHz, which covers most of the worldwide 5G mmWave frequency band candidates at the 20-GHz band range.