Low power location-tracking device with combined short-range and wide-area wireless and location capabilities

A personal monitoring communication device that is coupled with a person being monitored and is in communication with at least one monitoring and communication control device for monitoring and communicating with the person, wherein the personal monitoring communication device comprises:

• a panic button which the person being monitored can activate in an emergency;
• a short range wireless radio transmitter/receiver in communication with the at least one monitoring and communication control device;
• and
• an emergency beacon generator that is connected to the panic button which when pressed by a person being monitored activates the emergency beacon generator that generates an emergency beacon frequency hopping signal at a slow frequency hopping rate and including an arbitrarily long pseudorandom bit sequence for transfer to the short range wireless radio transmitter/receiver for transmission.

A personal monitoring communication device finder in communication with a personal monitoring communication device comprising:

• a receiver for acquiring the emergency beacon frequency hopping signal transmitted by the personal monitoring communication device;
• a slow frequency hopping sequence generator that provides a frequency sequence for the receiver that matches the slow frequency hopping rate to receive the emergency beacon frequency hopping signal;
• a frequency shift keying demodulator extracting a long pseudorandom bit sequence from the acquired emergency beacon frequency hopping signal;
• and
• a correlator in communication with the frequency shift keying demodulator to receive the extracted long pseudorandom bit sequence and a local version of the long pseudorandom bit sequence for determining a sampling absolute correlation value for the extracted long pseudorandom bit sequence and the local long pseudorandom bit sequence to determine an estimate of the distance of the personal monitoring communication device finder to the personal monitoring communication device transmitting the emergency beacon.

A dead reckoning circuit incorporated within a personal monitoring and communication device for determining the position of the person coupled to the personal monitoring communication device, the dead reckoning circuit comprising:

• a gyroscope for determining a direction that the person coupled to the personal monitoring communication device is moving;
• a three-axis accelerometer for determining an acceleration vector when the person moves;
• and
• integration unit in communication with the three axis accelerometer to receive the acceleration vector that double integrates the acceleration vector to determine a displacement from a reference location.

A battery power management circuit incorporated in on personal monitoring and communication device connected to a battery for minimizing power consumption to increase battery life of the battery powering the personal monitoring to communication device, wherein the battery power management circuit comprises:

• a battery power sensing device for determining an amount of power remaining in the battery;
• a function status monitor connected to a plurality of personal monitoring communication device circuits;
• and
• a state machine in communication with the battery power sensing device and the function status monitor to determine which of the personal monitoring communication device circuits may be deactivated or functionally degraded to conserve energy within the battery.