Electrostatic field simulation of variable pitch helical cathode

With the development of high power magnetron, cathode is researched a lot to endure higher temperature and intense electron bombardment. In order to decrease the central part temperature of cathode in magnetron and extend magnetron's lifetime, a kind of variable pitch helical cathode is proposed in this paper. Computer simulations are adopted to verify whether cathode surface electric field distribution is consistent with its structural uniformity. So electrostatic field uniformity of variable pitch helical cathode is simulated by CST-EM and compared with cylindrical cathode and even pitch helical cathode. The results show that thought variable pitch cathode has the worst structural uniformity, it has similar field uniformity to even pitch cathode, and the uniformity of electric field near the cathode surface of variable pitch cathode is relatively close to that of the cylindrical cathode. So it may be adopted in magnetrons to improve magnetrons' performance and extend their lifetime.