An embodiment of a system for wirelessly charging a wrist-worn device may include a radio frequency (RF) charging energy generating element, and an antenna configured to radiate the RF charging energy, the antenna comprising a first coil and a second coil, the first coil and the second coil each comprising a plurality of windings, the windings of the first coil being wound in a direction opposite the direction of the windings of the second coil. An embodiment of a wrist-worn charge-receiving device may include an antenna coil adapted to receive radio frequency (RF) charging energy, the antenna coil comprising non-uniform windings; and a rechargeable power source coupled to the antenna coil, the antenna coil adapted to provide the RF charging energy to the rechargeable power source.