A magnetic core antenna system including a magnetic core and a winding network. The winding network may be configured with a non-uniform ampere-turn distribution to achieve a desired flux density in the core. The network may include a plurality of windings configured to provide a winding impedance facilitating optimal transmitter power delivery to the windings. A magnetic core may be constructed from multiple components having longitudinal contact surfaces and joined by a transverse clamping force. An air gap may be provided between the components to allow relative movement therebetween.