Analysis of an array of two water-loaded modified box-horns for hyperthermia treatment of tumor

Abstract

In this paper, the theoretical analysis of fields in three-layered biomedia (skin, fat and muscle layers) in direct contact with an array of two modified box-horns suitable for hyperthermia treatment of cancerous tumor has been carried out using plane wave spectral technique. The proposed modified box-horn applicator has relatively uniform field distribution across the aperture as compared with flared horn of identical aperture dimensions. The modified box-horn is a novel applicator, in which the horn is flared in both E-and H-planes, while in conventional box-horn, the horn is flared only in H-plane. Each modified box-horn of the array is assumed filled with deionized water to reduce its size and to provide a better impedance match to a high dielectric constant medium representative of human skin. The specific absorption rate (SAR) distribution in different bio-layers (viz. skin, fat and muscle layers) are computed and presented at an ISM frequency of 2450 MHz. The results of SAR values in different layers for array of two modified boxhorns and single modified box-horn are calculated and compared for same output power. It is shown that an array of two modified box-horns gives relatively higher SAR values in different layers in comparison to single modified box-horn. The SAR distribution in different layers for an array of two conventional box-horns is also obtained and compared with that for an array of modified box-horns for same output power. The result with phase steering of the SAR pattern is also presented in the paper. The result has been validated against available published result in the literature.