Millimeter wave negative refractive index metamaterial antenna array.

Area of Science:

• Electromagnetics and Metamaterials
• Antenna Engineering
• Wireless Communications

Background:

• Metamaterials offer unique electromagnetic properties not found in natural materials.
• Negative refractive index metamaterials (NIMs) exhibit negative effective permittivity and permeability.
• Enhancing antenna gain is crucial for improving wireless communication system performance.

Purpose of the Study:

• To develop and characterize a novel NIM.
• To utilize the NIM to enhance the gain of a microstrip patch antenna (MPA).
• To demonstrate the versatility of the NIM for 5G millimeter wave applications.

Main Methods:

• A novel NIM exhibiting negative effective permittivity and permeability at 28 GHz was designed and fabricated.
• Two layers of 5x5 subwavelength NIM unit cell arrays were placed as a superstrate above a single MPA.
• The NIM array was also tested with a 2x2 array of MPAs to evaluate its performance in a multi-element antenna system.

Main Results:

• A gain increase of 7.9 dBi was observed for a single MPA using the NIM superstrate.
• The 2x2 MPA array with the NIM superstrate achieved a maximum gain of 13.5 dBi.
• Significant gain enhancements of 7.55 dB (E-Plane) and 7.25 dB (H-Plane) were measured at 28 GHz.

Conclusions:

• The developed NIM effectively enhances the gain of MPAs at millimeter wave frequencies.
• The proposed antenna structure demonstrates suitability for 5G millimeter wave communication systems.
• The NIM offers a promising solution for future millimeter wave access points and cellular base stations.