A Miniature Implanted Inverted-F Antenna for GPS Application

A miniature implanted Hilbert inverted-F antenna design at the 1.575 GHz global positioning system (GPS) frequency is proposed, which can be used to track the location of its user, e.g., the elderly with declining mental capacity (Alzheimer´s disease). A detailed parametric study of the antenna design is performed by considering it to be implanted within a human muscle model. The effects of the substrate, superstrate, and the nearby muscle tissue on antenna performance are carefully investigated. A laboratory prototype of the antenna was built and tested within a muscle equivalent fluid indicating good VSWR performance. Finally the said antenna when placed within the tissue equivalent fluid was also tested to track GPS satellites with the help of a low noise amplifier (LNA). Such field measurements demonstrate that the antenna can easily lock into six or more satellites which are more than enough to determine the location of a person.