Miniaturized Dual-Band Dipole Antenna Loaded with U-Shaped Arms

A miniaturized dual-band dipole-based planar antenna for mobile satellite service (MSS) is presented. Four pairs of U-shaped arms are added at the end of the dipole, which can reduce the antenna area to 0.18 λ
0
× 0.1 λ
0
. To improve impedance matching, a pair of trapezoidal structures are loaded at the feeding point. A prototype was designed, fabricated, and measured to verify the idea. Good agreement between the simulations and measurements is obtained. The measured 10-dB impedance bandwidths are 1.83% (1512-1540 MHz) and 1.69% (1647-1675 MHz), respectively, which can fully support the 7-MHz L-band MSS.