Pr. Chaudhari et Pb. Patil, EFFECT OF HIGHER-ORDER PERTURBATION TERMS ON THE PROPAGATION OF EM WAVES IN TWISTED RECTANGULAR WAVE-GUIDES, Indian Journal of Pure & Applied Physics, 32(8), 1994, pp. 655-659
The problem of propagation of dominant TE mode, in the twisted wavegui
de of rectangular cross-section is analysed up to 12th order perturbat
ion terms. The helical coordinate system is used for the mathematical
formulation of the problem and perturbation technique is used in obtai
ning the solution, It is shown that for, accuracy of the results the c
ontribution of higher order perturbation terms cannot be neglected. Th
e information about the percentage contribution of higher order terms
is worked out. This is useful in deciding the number of terms to be in
cluded for the expected accuracy.