Abstract: A combined proximity monitoring and locating system including a wearable unit, a proximity detector, and a control subsystem. The proximity detector includes a receiver for receiving the wearable unit transmitter signal, a processing subsystem configured to signal an alert if the wearable unit transmitter signal strength is below a pre-established minimum, and a tracking subsystem configured to assist in locating the wearable unit based on the signal strength of the wearable unit transmitter signal. A control subsystem is responsive to an indication that the alert has been signaled. The control subsystem includes an RF transmitter configured to transmit a transponder activation signal, and an RF antenna network for relaying the transponder activation signal to a receiver of the portable unit to activate the transponder thereof. A tracking unit includes a receiver configured to receive the transponder signal of the wearable unit to locate the wearable unit.

Abstract: An asset location, tracking, and recovery system and method includes a network of VHF towers and a control center receiving signals from and transmitting signals to the VHF towers. Primary locating units each include a transmitter, a receiver, and a transponder activated when a signal is transmitted by the control center via the VHF towers to the receiver. Auxiliary locating units include at least a transmitter emitting a signal received by at least one primary locating unit receiver which relays that signal to the control center via the VHF towers from the primary locating unit transmitter.

Abstract: A combined proximity monitoring and locating system including a wearable unit, a proximity detector, and a control subsystem. The proximity detector includes a receiver for receiving the wearable unit transmitter signal, a processing subsystem configured to signal an alert if the wearable unit transmitter signal strength is below a pre-established minimum, and a tracking subsystem configured to assist in locating the wearable unit based on the signal strength of the wearable unit transmitter signal. A control subsystem is responsive to an indication that the alert has been signaled. The control subsystem includes an RF transmitter configured to transmit a transponder activation signal, and an RF antenna network for relaying the transponder activation signal to a receiver of the portable unit to activate the transponder thereof. A tracking unit includes a receiver configured to receive the transponder signal of the wearable unit to locate the wearable unit.

Abstract: An asset location, tracking, and recovery system and method includes a network of VHF towers and a control center receiving signals from and transmitting signals to the VHF towers. Primary locating units each include a transmitter, a receiver, and a transponder activated when a signal is transmitted by the control center via the VHF towers to the receiver. Auxiliary locating units include at least a transmitter emitting a signal received by at least one primary locating unit receiver which relays that signal to the control center via the VHF towers from the primary locating unit transmitter.

Abstract: A vehicle-tracking radio transponder used in stolen vehicle recovery systems and in which the same transponder is also synergistically accessed for panic or emergency operator activation and for sensed unauthorized moving or starter circuit tampering independently of and without interfering with the stolen vehicle recovery command signal control of the transponder.