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Noori BniLam

Publications and source records attributed to Noori BniLam.

2 recordsLinked to original sources

A Superposition-Based Framework for Rapid Estimation of Arbitrary Antenna-Array Patterns

Antenna array theory is a well-established field. However, a systematic approach for fast pattern estimation in arrays with arbitrary antenna locations and orientations has not yet been developed. In this paper, based on simulated (or measured) radiation patterns of a single element, we present a Superposition-Based Framework (SBF) for numerically computing array radiation patterns in which the positions and orientations of the antenna elements can be readily modified. To validate the framework, a compact dual-layer circularly polarized patch antenna at 5.02 GHz (ESA's Celeste frequency) is designed and used as an array element in an 8-element ring antenna. Using the proposed framework and the single-element far-field pattern, the array radiation pattern is computed in 13s (excluding single-element simulation time), which is at least 50 times faster than the corresponding full-wave simulation while maintaining comparable accuracy. Comparisons with CST simulations show a peak E-field error of less than 0.5% for the intended polarization. Full-wave simulations are memory- and energy-intensive, and hence, impractical for larger arrays. The proposed SBF requires low computational power, making it energy-efficient and sustainable.

physics.app-ph↗

Phase-Center-Constrained Beamforming for Minimizing Phase-Center Displacement

Accurate knowledge and control of the phase center in antenna arrays is essential for high-precision applications such as Global Navigation Satellite Systems (GNSS), where even small displacements can introduce significant localization errors. Traditional beamforming techniques applied to array antennas often neglect the variation of the phase center, resulting in unwanted spatial shifts, and in consequence, localization errors. In this work, we propose a novel beamforming algorithm, called Phase-Center-Constrained Beamforming (PCCB), which explicitly minimizes the displacement of the phase center (Phase Center Offset, PCO) while preserving a chosen directional gain. We formulate the problem as a constrained optimization problem and incorporate regularization terms that enforce energy compactness and beampattern fidelity. The resulting PCCB approach allows for directional gain control and interference nulling while significantly reducing PCO displacement. Experimental validation using a simulated GNSS antenna array demonstrates that our PCCB approach achieves a fivefold reduction in PCO shift compared to the PCO shifts obtained when using conventional beamforming. A stability analysis across multiple random initializations confirms the robustness of our method and highlights the benefit of repeated optimization. These results indicate that our PCCB approach can serve as a practical and effective solution for decreasing phase center variability.

eess.SP↗