THE DOMINANT CUTOFF WAVELENGTH OF A LUNAR LINE
Abstract
A method is presented for caculating the lowest cut-off wavelength of a new microwave transmission line, lunar line, which is formed by 2 eccentric circular metal tubes, connected with a metal bar or tangential to each other. The lunarshaped cross section is approximated by introucing a series of steps in the outer guide wallAND IS DIVIDED INTO M FAN-SHAPE REGIONS. The solution of this multiple-step waveguide is carried out by introducing the parameter alpha sub i for individual regions. The radial boundary conditions require a combination of Bessel's functions of non-integer order for each region. The common boundaries between regions give m integral equations. These integral equations are solved by assuming an electric field at the common boundary. The solution of the m-stepped waveguide resuls in a system of 2 m eqations containing beta sub c, rho sub i, and alpha sub i, 2 m unknowns. A successive approximation method is applied to obtain the cut-off wavelength. The calculated value is in close agreement with experimental results. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1961
- Accession Number
- AD0260332
Entities
People
- Akira Ishimaru
- Ann Y. Hu
Organizations
- Boeing