(1) A circular waveguide with radius of 3 cm is made of copper (s = 5.76 ´ 107 S/m). For the dominant TE11 mode, determine the cutoff frequency and attenuation constant (in Np/m and dB/m) at a frequency of 7 GHz. Assume that the waveguide is filled with air.
(2) A circular cavity has a radius of 6 cm and a height of 10 cm. It is filled with a lossless dielectric with er = 4.
(a) Find the first three TE and/or TM modes according to their resonant frequency (in order of ascending values).
(b) Find the Q of the cavity (assuming dominant mode operation). The walls of the cavity are copper (s = 5.76 ´ 107 S/m).