Patent ID: 7046153

Claim:
A monitoring and locating device comprising: at least one portable child unit; and a parent unit in communication with the portable child unit, the parent unit being configured to assign an individual identifier to each portable child unit by wireless radio frequency signal and configured to monitor each of the portable child units by transmitting and receiving signals to each of the portable child units based on the individual identifiers assigned thereto the parent and child units being configured to provide directional information as to a position of the child units with respect to the parent unit and a perimeter alarm when the child unit moves to a distance from the parent unit that is greater than a predetermined distance; and a directional display coupled to a microprocessor constructed and arranged to display the position of a selected child unit relative to the parent unit based on phase differential signals generated by the microprocessor for the selected child unit; and an operating channel selection circuit coupled to the microprocessor, the operating channel selection circuit constructed and arranged to select an operating channel on a frequency band for the parent unit to transmit or receive thereon.