Experimental study of an inductively loaded short monopole antenna

Theoretical studies have shown that the properties of electrically short monopole antennas are improved by placing an inductive load on the structure. The results obtained from the moment method are presented and compared with an experimental evaluation. The current distribution along the structure is computed and measured for various positions of the load. From this, the input admittance, efficiency, and bandwidth of the antenna are deduced. It is found that the efficiency and the bandwidth of the antenna increase as the load is moved from the base of the monopole until a maximum is reached. Simultaneously, the value of the inductance required to tune the monopole increases as the latter is moved away from the base.