Personal tracking device with low power consumption

An portable tracking device integrating a mobile phone module (e.g. based on GSM or 3G networks), a GPS module, a radio Beacon and ultrasonic beacon. The tracking device is normally in a hibernated state when the entire device consumes little energy and require no periodically changing or recharging batteries to power the device. It consumes power from the primary battery only when a tracking process is actually taken place. With this portable tracking device on the person who is unable to affirmatively report his or her whereabout, the remote center and/or a search team can communicate the GPS module, radio beacon and ultrasonic beacon of the tracking device via the mobile phone module based on existing wireless communication technologies, such SMS, GPRS, ect, on GSM or 3 G networks, which also serves as a means of initial rough estimation of the tracking device's location.