Comparative TE modal analysis and extended parameter calculations of magnetronwall waveguide for gyropeniotron applications
Abstract
Accurate determination of the magnetronwall waveguide modal content is approached by examining the waveguide transverse cutoff constant (for which no closedform analytic solution is known). The method of solution involves dividing the waveguide into two regions, an inner (circular) region and an outer (slot) region, assuming a constant electric field at the common interface, and equating the impedance functions at the interface. Computer calculations include large ratios of outertoinner wall radii (20:1), normalized slot angles between 0.01 and 0.99, a variable number of vanes (230), and higherorder modes that have not been previously reported. Mode numbering of the higherorder modes is also considered. The TE mode spectrum is plotted as a function of waveguide geometry. A waveguide model was built, and frequency resonances were measured. Resonances were correlated using a scanning filter computer program and used to calculate the modal cutoff frequencies. Experimental data agree with calculated values to within 1.25, 0.57, 0.49, and 2.48 percent for the four modes detected thus far. Results for lowestorder modes agree with those of other investigators to within about 5 percent or better in most instances.
 Publication:

IEEE Transactions on Electron Devices
 Pub Date:
 September 1989
 DOI:
 10.1109/16.34280
 Bibcode:
 1989ITED...36.1976P
 Keywords:

 Cavity Resonators;
 Circular Waveguides;
 Frequency Response;
 Magnetrons;
 Microwave Tubes;
 Modal Response;
 Iterative Solution;
 Resonant Frequencies;
 Vanes;
 Electronics and Electrical Engineering