0.65–7 GHz ultra-wideband spherical self-complementary antenna

We propose a spherical ultra-wideband antenna based on the self-complementary structure. The antenna employs a loop comprising of two symmetric teardrop shaped arms conformally printed on a three-dimensional sphere. To enhance the impedance matching bandwidth, the capacitive and inductive loading techniques are applied by broadening the antenna's front part and adding shorting strips at the rear part, respectively. Simulation and measurement results show that the proposed antenna is capable of covering the frequency range of 0.65-7 GHz which is suitable as a testing antenna in a mobile handset measurement chamber.