This study presents an optimized ultra-wideband (UWB) Vivaldi antenna engineered for high gain, narrow beamwidth, and superior impedance matching, specifically designed for Through-the-Wall Imaging Radar (TWIR) systems. Fabricated on a cost-effective 0.8-mm-thick FR-4 substrate with dimensions of 148 mm × 85 mm, the antenna incorporates ten open-ended rectangular slits on each arm of the exponentially tapered slot and nine metallic strips at the slot’s end. Through extensive parametric optimization and precise positioning, this configuration uniquely enhances gain by 51% at lower frequencies and 35% at 4 GHz compared to conventional designs, peaking at 12.59 dBi. Operating across 1.9 to 4.5 GHz, it delivers gains exceeding 7 dBi from 2.3 to 4.5 GHz and a narrow beamwidth down to 29.3° at 4 GHz. Validated by CST Microwave Studio simulations and measurements, this antenna outperforms existing TWIR-focused Vivaldi designs in penetration and resolution, making it an exceptional candidate for advanced radar imaging applications.
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Mohammadjany, A. , & Miar-Naimi, H. (2026). A High-Gain, Low CRR, Narrow beam width Enhanced Vivaldi Antenna for Through-the- Wall Imaging Radar. Contributions of Science and Technology for Engineering, 3(1), 1-9. doi: 10.22080/cste.2025.29067.1035
MLA
Armin Mohammadjany; Hossein Miar-Naimi. "A High-Gain, Low CRR, Narrow beam width Enhanced Vivaldi Antenna for Through-the- Wall Imaging Radar", Contributions of Science and Technology for Engineering, 3, 1, 2026, 1-9. doi: 10.22080/cste.2025.29067.1035
HARVARD
Mohammadjany, A., Miar-Naimi, H. (2026). 'A High-Gain, Low CRR, Narrow beam width Enhanced Vivaldi Antenna for Through-the- Wall Imaging Radar', Contributions of Science and Technology for Engineering, 3(1), pp. 1-9. doi: 10.22080/cste.2025.29067.1035
CHICAGO
A. Mohammadjany and H. Miar-Naimi, "A High-Gain, Low CRR, Narrow beam width Enhanced Vivaldi Antenna for Through-the- Wall Imaging Radar," Contributions of Science and Technology for Engineering, 3 1 (2026): 1-9, doi: 10.22080/cste.2025.29067.1035
VANCOUVER
Mohammadjany, A., Miar-Naimi, H. A High-Gain, Low CRR, Narrow beam width Enhanced Vivaldi Antenna for Through-the- Wall Imaging Radar. Contributions of Science and Technology for Engineering, 2026; 3(1): 1-9. doi: 10.22080/cste.2025.29067.1035
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