A Low Profile Miniaturization Low Frequency Wideband Antenna Using Passive Lumped Elements Loading

In this paper, a low profile miniaturization low frequency sleeve monopole antenna loaded with passive lumped (PL) elements is proposed, which can be utilized for HF, VHF, UHF, and P band applications. The proposed antenna is fed by coplanar waveguide (CPW) and composed of feeding line, modified T-shaped radiation patch, sleeve structure and loaded passive lumped elements. An original monopole antenna is operating at 231 MHz with a small fractional bandwidth of 31.8%. By modifying the T-shaped radiation patch and adding the sleeve structure, the fractional bandwidth can be improved by 11%. To further enhance its performance, several passive lumped elements are integrated with the antenna. The design procedure is presented and analyzed in detail. The simulated results demonstrate that a fractional bandwidth of 192.2% from 10-500 MHz can be achieved for the proposed antenna system, which is also in agreement with the measured result.