Simulation of a portable microwave breast cancer detection system and derivation of a mathematical model for the relative electromagnetic fields
Loading...
Date
2021
Authors
Nath, Debarati
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Breast microwave imaging (BMI) systems open a new era for detecting breast cancer because of their advantages like non-ionizing radiation and cost-effectiveness. However, Low- and Middle-Income countries (LMIC) have limited options to make frequent accesses for those existing Microwave breast cancer detection devices. This study worked on the simulated microwave breast cancer detection system to make the microwave device portable, and user-friendly. The proposed portable system with a transmitter, a sensing chamber, and a receiver array was simulated in the CST Microwave solver. A horn antenna used as the transmitter was designed using the same characteristics of the horn antenna used in the laboratory and a 90% bandwidth agreement at -10dB between the simulated and measured reflection coefficient was acquired. 37 points on the receiver array were used instead of designing independent antennas as receivers for avoiding design complexities. The effects of a point-like scatterer (Al rod) on the relative electromagnetic (EM) fields were analyzed to improve the design and performances of the portable system. The ratios of E-field intensities to the open-space E-field intensities were evaluated as a function of frequencies and rod positions in the sensing chamber. A mathematical equation was derived to explain the characteristics of the relative EM strength because of the presence of the Al rod. A robust multi-dimensional fitting procedure was used to establish an agreement of -1.3% ± 10% between the fitted and simulated data. r2 = 0.92 with p < 0.01 was obtained for rod positions within ± 6 cm in both x and y- directions and frequencies from 2-8 GHz. The values of parameters of the proposed mathematical equation were evaluated and the theoretical explanations were established. The analytical approach with the analysis on EM field strength with rod positions will allow to produce data for transfer learning of machine learning networks and enable optimal antenna placement.
Description
Keywords
Breast Cancer, Microwave, E-fields, Mathematical Modeling