Fast quasi-null-filling of radiation patterns for multiple solutions generation

• Published in: Scientific reports Vol. 14; no. 1; pp. 3885 - 8
• Main Authors: López-Álvarez, Cibrán, López-Martín, María Elena, Rodríguez-González, Juan Antonio, Ares-Pena, Francisco José
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 16.02.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 639/166/987; 639/766/25; Arrays; Convex analysis; Humanities and Social Sciences; multidisciplinary; Optimization; Radiation; Science; Science (multidisciplinary)
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-54497-9

Here we present an improved, rapid method for filling quasi-nulls in symmetrical radiation patterns synthesized by equispaced linear arrays, leading to the generation of multiple solutions. Considering the polynomial representation of the pattern, this null-filling is achieved by displacing the roots radially off the unit circle, keeping a constant displacement. This allows analyzing how the potential solutions vary with the quasi-uniform filling and the associated directivity loss. This method is based on the Cardano-Vieta relations, which link the coefficients of a complex Schelkunoff polynomial with its roots. As examples of application, we have considered a 20/100 element Dolph-Chebyshev pattern, with a spacing between the elements λ / 2 , side lobe level of − 20/− 28 dB and three inner sidelobes at − 40/− 50 dB.