Radio Science

Guided electromagnetic waves in a curved rectangular mine tunnel


  • Samir F. Mahmoud,

  • James R. Wait


The transmission of VHF electromagnetic waves in a curved mine tunnel is analyzed using an idealized model in a cylindrical geometry. The tunnel cross section is assumed to be rectangular and the broad curved walls are imperfectly reflecting. The computations of the modal characteristics are facilitated by using a modified Airy function approximation of the rigorous cylindrical wave functions. The results indicated that the curvature of such tunnels will seriously increase the attenuation of the dominant low-order modes that are used for communications.