Yohandri, F.A. Haqqi, F. Andriani
This paper presents the design and analysis of a power-weighted feeding network to achieve sidelobe level reduction in an elliptical microstrip array antenna for Circularly Polarized Synthetic Aperture Radar (CP-SAR) sensors. The proposed network applies Chebyshev polynomial-based amplitude weighting to realize non-uniform power distribution among array elements, effectively shaping the radiation pattern while maintaining circular polarization. The Method of Moments (MoM) is utilized to optimize the excitation amplitudes and phases for the L-band operating frequency. Simulation results show an axial ratio bandwidth of 11.2 MHz (0.88%), closely matching the measured 13.3 MHz (1.05%). The proposed feeding network achieves sidelobe suppression of about 21.4 dB (simulated) and 23.3 dB (measured), consistent with the 20 dB Chebyshev design target. These results demonstrate that precise feed amplitude control significantly improves antenna performance and fulfills CP-SAR operational requirements. © PIERS-FALL 2025.All rights reserved.
Physics Department, Universitas Negeri Padang, Kampus UNP Jl. Prof. Hamka Air Tawar, West Sumatera, Padang, 25131, Indonesia; Vocational School, Universitas Negeri Padang, Kampus UNP Jl. Prof. Hamka Air Tawar, West Sumatera, Padang, 25131, Indonesia
