# Solved Problems-2

Problem-2

A parallel plane waveguide consists of two shells of good conductors separated by 10 cm. Find the propagation constant at frequencies of 100 MHz and 10 GHz when operated in

*TE*_{1}mode. Does the wave propagate in each case?Solution

Here,
Hence, the propagation constant is given as,
Since,
At frequency,
At frequency,
At frequency,

*a*= 10 cm = 0.1 m, and for*TE*_{1}mode,*n*= 1*f*= 100 MHz,*f*= 10 GHz,*f*= 100 MHz, the propagation constant is real, i.e., phase shift is zero So, wave propagation does not take place at this frequency. However, at frequency,*f*= 10 GHz, the propagation constant is imaginary, i.e. . So, wave propagation takes place at this frequency.