| The conventional treatments of brain tumors include manipulation, chemotherapy, immunization, etc, which have some limitations. Hyperthermia treatments make use of thermal effects of some heat sources, like radio-frequency (RF) electromagnetic waves, microwaves or ultrasound, to heat up tumor area or the whole body and keep the effective temperature for some time. It makes instant metabolism of tumor tissue, which leading to molecular structure changes in tumor cells and lysosomal reactivity enhancements, to the purpose of killing tumor cells and charming off tumors.In this paper, the automatic brain tumors therapeutic equipment bases on the principle of RF hyperthermia. It heats up tumor tissue smoothly and uniformly by a certain frequency radio signal, and ultimately maintains the temperature at an expected level. Because of its selective warming, cancer cells with ischemia, hypoxia, over acid and lysosome can be damaged intensively.The main work includes general program design, RF signal circuit design, safety control system design, application programming and performing automatic hyperthermia.RF signal circuit generates a stable sinusoidal signal at 13.56MHz frequency, which is amplified by intermediate step amplifying circuit and RF amplifier. This signal passes through matching networks and the branch box and then outputs to electronic probe. The probe should be built in tumor area to heat up slowly. In the manual treatment, output power should be adjusted slowly, which leading smooth rises in tumor temperature. In automatic treatment, output power is specified and controlled by application program in computer. For best results, the temperature in tumor tissue maintains at 43℃for about an hour. Power and temperature measuring and control system, and power supply safety circuit make up of the core of safety control system, which improves the safety of therapeutic equipment effectively.
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