The calculated phase velocity of long end-fire uniform dipole arrays

Surface waves have been applied recently to the study of end-fire arrays. An important step in the theory of surface-wave antennas is the calculation of the local phase velocity of the surface wave from the antenna geometry. While experimental work has been done along this line, no adequate theoretical solution seems to be available. In this report, a mathematical procedure is presented for obtaining an approximate value of the phase velocity for long end-fire uniform dipole arrays, as a function of the antenna geometry. Results have been reported for a number of geometrical parameters and curves plotted to facilitate the analysis and design of arrays. The results have been compared with experimental measurements and an explanation has been given for the discrepancies found; finally, a criterion for correcting the results has been outlined.