Research On Medical Radio Frequency Array Antenna Technology

With the continuous progress of science and technology,microwave hyperthermia has been applied in many clinical treatment of the disease.Clinical studies have shown that in some medical treatments,hyperthermia is more effective than other treatments,such as tumor hyperthermia,rehabilitation physiotherapy,gynecology and some other diseases,and so on.Compared with other treatment methods,microwave thermotherapy has the advantages with no anesthesia,convenient,safe,no side effects and any more.In the development of microwave thermal therapy,the design of safe and reliable microwave thermotherapy antenna has been an important aspect of microwave hyperthermia technology.Based on the principle of microwave hyperthermia and the theory of microstrip antenna,a focusing microstrip antenna for microwave hyperthermia was designed by means of electromagnetic simulation software HFSS.The main work includes:1.A conformal focused microstrip antenna with a good focus effect was designed for the human arm and leg tissue.The single microstrip antenna was designed by using the miniaturization technique of the antenna,and the array antenna was arranged in the form of 3 × 4,whose appearance was semi-hexagonal and worked at 912 MHz.Each unit was feed by coaxial line and had a separate feed port,eliminating the need for a complex feed system.2.The electric field distribution of different number of working antenna elements was simulated,and analyzed the corresponding focusing area and the applicable situation.In order to realize the change of the size and position of the focusing area,the way of phase control of the selected antenna was chose based on the phased array theory to form the energy convergence in the target area.The simulation results showed that the array antenna can realize the variability of the size and position of the focusing area,with a total of 12 kinds of focus states were realized,which can be used for different situations.3.According to the structure of the microwave hyperthermia instrument,selected the signal source which can generate microwave at 912 MHz,designed the tested power splitter and the amplifier,then a simple microwave hyperthermia system was built to verify the performance of semi-hexagonal array antenna.For antenna elements that require phase control,this paper used different lengths of coaxial line for feeding to achieve different positions of the corresponding positions.The test results showed the array antenna could realize 12 kinds of focus states.To make further research on microwave hyperthermia antenna,the expectation was made at the end in this paper.