1 views

An air-filled rectangular waveguide has inner dimensions of $3 \mathrm{~cm} \times 2 \mathrm{~cm}$. The wave impedance of the $\mathrm{TE}_{20}$ mode of propagation in the waveguide at a frequency of $30 \; \mathrm{GHz}$ is (free space impedance $\eta_{0}=377 \; \Omega$ )

1. $308 \; \Omega$
2. $355 \; \Omega$
3. $400 \; \Omega$
4. $461 \; \Omega$