A full Ka band gap waveguide based slot array antenna with 45° slant polarization

Area of Science:

• Electromagnetics and Antenna Engineering
• Microwave and Millimeter-Wave Technology

Background:

• Ka-band applications require high-performance antennas with wide bandwidth and high gain.
• Traditional antenna designs often face challenges with electromagnetic energy leakage and efficiency at millimeter-wave frequencies.

Purpose of the Study:

• To develop a very wideband, 45° slant-polarized, 8x8 element slot antenna array for Ka-band applications.
• To utilize gap waveguide technology to suppress electromagnetic energy leakage and enhance antenna gain and efficiency.

Main Methods:

• Design and fabrication of an 8x8 element slot antenna array utilizing gap waveguide technology.
• Implementation of a novel two-layer feed network with folded E-plane groove gap waveguide power dividers.
• Experimental testing to validate antenna performance parameters.

Main Results:

• Achieved a reflection coefficient better than -10 dB across the 26.35-40 GHz Ka-band.
• Demonstrated a peak gain of 26.9 dB with high efficiency due to low-loss gap waveguide characteristics.
• Measured sidelobe level (SLL) and cross-polarization discrimination (XPD) better than -24.1 dB and 25.6 dB, respectively.

Conclusions:

• The proposed E-plane groove gap waveguide-based antenna array offers a low-profile, low-loss, and wideband solution for Ka-band and millimeter-wave frequencies.
• The 45° slant polarization and gap waveguide integration enable superior performance in terms of gain, efficiency, and isolation.
• This antenna array is suitable for advanced communication systems operating in the Ka-band spectrum.