New three-dimensional (3D) printing techniques enable the integration of an antenna directly onto the package of a small wireless sensor node. This volume-filling approach ensures near-optimal bandwidth performance of the small antenna, increasing a system’s battery life, data rate or range.
Simulated results show that the fabricated spherical antenna’s bandwidth-efficiency product is more than half of the fundamental limit and radiation pattern measurements exhibit a dipole pattern with -0.7 dBi gain.