Microstrip patch antenna with integrated adaptive tuning

Printed antennas mounted inside mobile communications equipment experience some detuning due to changes in the external environment. Such detuning can be offset by using a varactor tuned antenna. In this paper varactor tuning is integrated with a diode detector to monitor external effects. PC mounted software is then used to allow adaptive retuning. Although successful automatic retuning is achieved, significant intermodulation products due to these non-linear devices are present