Discrete Source Optimization for Microwave Hyperthermia Using Quantum Annealing

This letter reports the optimal solution for microwave hyperthermia. Conventionally, the operating frequency of the hyperthermia has been chosen as one of the industrial, scientific, and medicine radio bands. For the selected frequency, the excitation of multiple discrete sources for hyperthermia has been optimized via various classical computing algorithms. In contrast, this letter includes the operating frequency in the list of optimization parameters. For eight evenly-distributed dipole sources around the body, it turns out that the optimal frequency lies in a few hundred MHz. Furthermore, we report that such an optimization can be accomplished with quantum annealing. The accuracy of quantum annealing is validated with the classical counterparts. This work reveals the potential for expanding the application of quantum annealing into the field of electromagnetic engineering.

I. Introduction

Hyperthermia refers to the therapeutic technique of raising the temperature of a specific region within a body. The primary challenge of hyperthermia lies in concentrating the electromagnetic fields precisely on the target lesions while minimizing their impact on other healthy tissues. Previous studies have used various optimization methods to decide the excitations of discrete sources [1], [2], [3], [4], [5], [6], [7], [8]. Nevertheless, the optimal frequency to apply the hyperthermia is still controversial, so the operating frequencies of the proposed applicators are diverse among the industrial, scientific, and medicine (ISM) bands as 13.56 [1], [2], 434, and 915 MHz [3], [4], [5], [6], and even a few GHz [8], [9].