The curved waveguides of various cross sections are very useful in building a waveguide system and are required in many communication applications, especially in satellite communications. While designing curved waveguides it is necessary to take care about exact position of axis and angle of bending for proper distribution of electric and magnetic fields. So that electromagnetic waves can propagate through waveguide in the desired manner. The problem of propagation of dominant TE mode in curved waveguide of right isosceles triangular cross-section is analyzed up to third order perturbation terms. The cylindrical coordinate system is used for mathematical formulation of the problem and perturbation technique is used in obtaining the solution. The information about the percentage contribution up to third order terms is worked out. It is shown that the propagation of electromagnetic waves through triangular waveguide and its phase velocity depends on the sense of bending of waveguide and frequency.
