Title :
Cross-coupling between open-ended coaxial radiators
Author_Institution :
Div. of Radiophys., CSIRO, Epping, NSW, Australia
fDate :
8/1/1996 12:00:00 AM
Abstract :
A solution is given for the problem of cross-coupling between a pair of open-ended coaxial cables, excited in the TEM mode and terminating in a ground plane. New integral and series representations are derived for the mutual admittance of the TEM modes, and useful low frequency and far-field approximations are found. Computed results are given for several examples of cables radiating into lossless dielectric media. Measured data is given for a pair of cables radiating in air and computed results agree very well over a wide frequency range. These results show the coupling coefficient increasing initially with frequency, in contrast to waveguide radiators where the coupling coefficient mainly decreases with frequency; the levels attained are significant, particularly above the cut-off of the TE11 mode. Cross-coupling is shown to be greatest when the inner-to-outer conductor ratio is about 0.53. The solution should be useful for analysing arrays of coaxial horns and obtaining the permittivity and permeability of materials
Keywords :
antenna arrays; approximation theory; cable testing; coaxial cables; dielectric materials; electric admittance; electromagnetic interference; horn antennas; integral equations; permeability; permittivity; series (mathematics); transmission line theory; EMI; LF approximation; TEM mode; TEM modes; air; coaxial horn arrays; coupling coefficient; cross coupling; cut-off; far field approximation; frequency range; ground plane termination; inner to outer conductor ratio; integral representation; lossless dielectric media; measured data; mutual admittance; open ended coaxial cables; open ended coaxial radiators; permeability; permittivity; series representation; waveguide radiators;
Journal_Title :
Microwaves, Antennas and Propagation, IEE Proceedings
DOI :
10.1049/ip-map:19960443