Wideband planar folded monopole antenna with tapered resistively loadings

A wideband planar folded monopole antenna with resistively loadings is proposed. This antenna is designed to cover the extremely wide frequency region, 30 MHz to 2000 MHz. By locating loadings at the upper part of the antenna, the loaded monopole antenna operates as a travelling-wave antenna. In addition, to reduce the total length of the monopole, upper part of the antenna is folded. A width of the line, a total length, a folded length, and the distance between the lines are optimized. Moreover, the wideband RF transformer is utilized. Due to the operating range of this transformer, VSWR of the fabricated antenna becomes worse than that of the simulation at the high frequency region. In case of the ideal impedance transformer, a measured VSWR of the proposed antenna agrees well with the simulated values. Therefore, additional research about a low-loss transformer operating in required bands should be performed to obtain the similar measured result close to the simulated one. From these results, the proposed antenna geometry can be applicable for the broadband wireless communication systems, especially in military vehicle antenna systems.