Polynomial approximation of current along thin symmetrical cylindrical dipoles

Current distributions and admittances of an isolated symmetrical cylindrical dipole, and of two nonstaggered parallel dipoles, are analysed using a polynomial approximation for current along the dipoles. For antennas of lengths less than or not greatly exceeding the free-space wavelength, a polynomial of only second order approximates the current distribution quite closely, and results in self and mutual admittances which are, on average, as accurate as those according to the Chang¿King 5-term theory. For longer antennas, of lengths up to approximately 1.5¿, a polynomial of only third order is an excellent approximation.