Tracking and communications device

摘要

A portable tracking and communications device (10) comprises a Global Positioning System (GPS) module and a mobile telephony module, the device including at least a first passive, electronic ground plane simulator comprising a pair of essentially grounded antennae (16, 17) that are selectively connectable one to the other via a parallel-connected resistor-capacitance resonator (18, 19), the resonator being tuned to a first predetermined frequency or frequency range.

主权项

1. A device comprising:
a housing; a Global Positioning System (GPS) module including a casing; a mobile telephony module including a casing; memory configured to store a mapping perimeter; a processor configured to determine whether the device lies inside or outside the mapping perimeter; a first circuit comprising a plurality of antennae each grounded to the housing, wherein the plurality of antennae are selectively connectable in parallel to each other with circuitry including a resistor-capacitor resonator; and wherein: the resistor-capacitor resonator is tuned to at least one of a first predetermined frequency or a first predetermined frequency range; the circuit is configured to provide mobile telephony signals in the device when the plurality of antennae are not connected to one another; the circuit is configured to provide GPS signals when the plurality of antennae are connected to one another the casing of the GPS module; and the casing of the mobile telephony module comprise the plurality of antennae.