A method is presented for determining continuous impedance loading along a cylindrical antenna of given dimensions, which approximately results in certain desired properties of the antenna. The essence of the method consists in assuming a dependence of the impedance loading on the length of the antenna, in the form of power series with unknown coefficients, and determining these coefficients by minimising a convenient function. Numerical examples show good agreement between computed results and available experimental data, and indicate that antennas having different desired properties can efficiently be synthesised by this method.