Low-Cost High-Gain Transmitarray with Beam-Scanning Enhancement Based on Hybrid Phase Distribution Method

Area of Science:

• Electromagnetics and Antenna Theory
• Metamaterials and Metasurfaces
• Wireless Communication Systems

Background:

• Transmitarrays offer advantages in antenna systems but often face limitations in beam-scanning range and efficiency.
• Achieving wide-angle beam-scanning typically requires complex feed systems or specialized unit cell designs.

Purpose of the Study:

• To introduce a novel hybrid phase distribution (HPD) method for enhancing the beam-scanning capabilities of multi-feed transmitarrays.
• To design and validate a low-cost, high-gain transmitarray antenna with wide-angle beam-scanning performance.

Main Methods:

• A hybrid phase distribution (HPD) method was developed, combining single-focal and bifocal principles tailored to feed illumination.
• A three-layer polarization conversion unit cell was designed for high-efficiency transmission and 360° phase coverage.
• A single-polarized transmitarray antenna was designed and simulated using the HPD method with a focal diameter ratio of 0.28.

Main Results:

• The proposed HPD method accurately determined phase distributions, reducing errors for various scanning angles.
• The designed transmitarray achieved a discrete ±60° beam-scanning range with a peak gain of 24 dBi.
• Low gain loss (0.7 dB at ±30°, 4.7 dB at ±60°) and excellent cross-polarization levels (below -35 dB) were demonstrated.

Conclusions:

• The HPD method effectively enhances the beam-scanning range of transmitarrays.
• The developed transmitarray antenna exhibits high gain, wide scanning angles, low cost, and a low profile.
• Experimental validation confirmed simulation results, highlighting the practical applicability of the design.