Abstract: Portable communication device and method for mitigating interference. One example portable communication device includes a frequency-modulated (FM) communication subsystem, a cellular communication subsystem, a first electronic processor, and a second electronic processor. The FM communication subsystem includes an FM modem and at least one FM antenna. The cellular communication subsystem includes a plurality of cellular antennas, a plurality of antenna tuners, and a cellular modem. The first electronic processor is configured to generate an alert signal responsive to detecting one of an audio signal reception by the FM communication subsystem and an audio signal transmission by the FM communication subsystem. The second electronic processor is configured to receive the alert signal from the first electronic processor. The second electronic processor is also configured to responsively cause the cellular communication subsystem to set substantially constant impedances for the plurality of cellular antennas.

Abstract: A circuit takes advantage of the voltage square times capacitance function of a capacitor to sustain output power during input power interruption with a smaller energy storage capacitor. The circuit comprises an N channel power MOSFET switch, a voltage blocking diode, an energy storage capacitor, a voltage sensing circuit and a capacitor/diode network to provide a constant MOSFET drive.