SAR optimization for multi-dipole antenna array with regard to local hyperthermia

Abstract

The following paper describes the valid optimization problem of multi-element circular array that contains 16 equal-length dipole antennas surrounding given two-spherical object. The task of the authors was to maximize the specific absorption rate (SAR) inside the inner object, while maintaining its minimum value in the external sphere. The proposed approach includes changes in the powers and phases of the voltage sources supplying individual dipoles of the antenna matrix. The shown method may have huge impact in localized tumor heating during thermal therapy. Streszczenie. Niniejsza praca opisuje ważny problem optymalizacji wieloelementowego szyku kołowego, który zawiera 16 anten dipolowych, o równej długości, otaczających dwu-sferyczny obiekt. Zadaniem autorów była maksymalizacja współczynnika absorpcji własnej (SAR) w wewnętrznym obiekcie, przy zachowaniu jego minimalnej wartości w zewnętrznej kuli. Zaproponowane podejście uwzględnia zmiany mocy i faz źródeł napięciowych zasilających poszczególne dipole szyku antenowego. Przedstawiona metoda może mieć olbrzymi wpływ na zlokalizowane grzanie guza podczas terapii ciepłem. (Optymalizacja współczynnika SAR dla szyku z wieloma antenami dipolowymi pod kątem hipertermii miejscowej)

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