Investigation of Millimeter-Wave Band Magnetron Dispersion Characteristics

Considered in this paper is the influence of electrode temperature on dispersion characteristics of millimeter-wave band magnetron. Cavity resonators without straps were used in millimeter-wave band magnetrons. In this case such systems have resonance equation as, Y_r + Y_n = 0, where Y_r-cavity impedance, Y_n -interaction space impedance. The impedance of both interaction space and cavity has been defined. Dispersion characteristics of millimeter-wave band magnetron have been investigated. Calculation results are shown. The electrodes investigation devices have changed geometrical dimensions for anode, high and width slot cavity and for secondary cathode. Rz=Rz(1+Deltat) (2) R_K=R_Kldr(l + Deltat)/pi where Delta-temperature expansion factor. This factor is different to anode and cathode. They have been determined separately. Dispersion characteristics of millimeter-wave band magnetron are presented for the case when temperature of both electrodes´ is equal ~27degC, for the case when cathode and anode temperature is increased up to ~100degC and for the case when anode temperature is increased up to ~100degC, and cathode temperature is increased up to ~600degC. Using this method calculated accuracy has been achieved no more 5 % compared with experimental results. Separation of magnetron oscillation were changed from 5 to 14 % for different millimeter-wave band devices when the secondary cathode temperature has been changed from 27degC to 250deg C.