A short broadband monopole antenna

A novel design procedure is proposed to overcome the narrow bandwidth characteristic of the monopole antenna. Having sections with different lengths and radii as well as adding loads at two points along the antenna makes it permissible to optimize the radiation efficiency and bandwidth of the monopole antenna. Particle swarm optimization (PSO) technique is used to determine the load values, their respective locations and the elements of the matching network. A bandwidth ratio of 5:l within the frequency range of 100-500 MHz is achieved. The total length of the antenna is 35 cm and the matching network is capable of handling RF power up to 100 W. The whole system is simulated with CST and ADS software. Measurement results of the fabricated antenna are in good agreement with simulations.