Compact antennas afford hemispherical coverage at any linear polarization.

Printed multi-turn loop antennas have been designed for contactless powering of, and reception of radio signals transmitted by, surgically implantable biotelemetric sensor units operating at frequencies in the vicinity of 300 MHz. In the original intended application of these antennas, the sensor units would be microelectromechanical systems (MEMS)-based devices now being developed for monitoring physiological parameters of humans during space flights. However, these antennas and the sensor units could just as well be used for physiological monitoring on Earth.