A Novel Antenna System for Body Temperature Change Detection Appropriate for Multi-Channel Microwave Radiometry

Abstract

Abstract-A planar inverted F antenna is combined with passive (reactively loaded) elements in order to implement a multi-frequency configuration appropriate for biomedical applications in microwave frequencies. A case study of an electronically Reconfigurable PIFA (R-PIFA) is pursued for the detection of temperature abnormalities in human tissue phantom using microwave radiometry, where the performance of the structure is optimized with respect to input impedance matching in multiple frequencies. The optimization of the array is performed using a Genetic Algorithm (GA) tool as a method of choice. Due to its limited physical size, the proposed R-PIFA can also be used as a portable antenna system for deployment in mobile medical applications.

Hybrid method of moments – induced EMF method for analysing multi‐element planar inverted F antenna arrays

“…We present an algorithmic method of calculating the mutual impedance and consequently the radiation pattern of multi-element PIFA array. Using the SuperNEC software only for calculating the Z in of a single element, and then using the (8) and (9) and the antenna theory, we can design the radiation pattern including the mutual coupling of the antenna elements as it is depicted in Fig. 10.…”

“…The main idea of this paper is to implement one simple element antenna (basic PIFA) and study its characteristics extracted from a simulation program. Afterwards two identical antennas (previously referred) are placed in the same level at a specific distance and studied how these characteristics are changed with the distance using the method of moments (MoM) in SuperNEC simulation program to estimate these results [5][6][7][8][9][10]. Finally and with the antenna theory using the induced electro-motive force (EMF) method we form an algorithm to prevent the radiation pattern and the input impedance of Melement PIFA array, reducing the simulation time because we only simulate the two elements PIFA (and solving an M × M equations system) and not simulate the M-elements array.…”

Auto Reconfigurable Patch Antenna for Biomedical Single Channel Multi-Frequency Microwave Radiometry Applications

“…Using the same methodology as the previous work of the authors [13] a better antenna structure is achieved (dimensions W : 0.046 m×L: 0.054 m×H: 0.0083 m) with an operative range between 1200 MHz-6650 MHz (depending on the values of the varactor diodes). A GA is capable of facing multi-variable problems, such as the design and synthesis of antennas, where a set of performance conditions (e.g., input impedance) should be satisfied.…”

“…As described before and in case of a single channel measurement, the dielectric properties of the medium change (shift) the central frequency (the frequency in which we have matching the input impedance) of the channel, so if we have a common antenna system the measurement would not be accurate, and we use the reconfigurable concept of a previous work of the authors [13] in which a set of varactor diodes are used to change the resonant frequency on demand [14][15][16].…”