Abstract: A wearable alert device includes an audio transducer and driver circuit that allows selection of either a high or low volume setting for driving the transducer. The driver circuit is operable in a single ended mode for low volume and a double ended mode for high volume. The single ended mode holds one terminal of the transducer low while the other is driven in correspondence with a clock signal, while the double ended mode drives one terminal in correspondence with the clock signal and the other terminal is inverted from the clock signal. The transducer is activated in response to an alert event, and can be driven according to a profile or pattern.

Abstract: A host and a communicatively linked paired tag can be identified. The tag can be associated with a tracked entity. The tag can be a low power computing device which can provide a location of a tracked entity to the host. An out of range condition can be detected. The condition can result in communication between the host and the tag being temporarily interrupted. A last location of the tag can be established. A set of hosts proximate to the last location can be determined. The set of hosts can be queried to determine if the hosts have received an advertisement message from the tag. Each of the set of hosts can be linked to a different paired tag. A notification can be conveyed to the host when the set of hosts receives the message from the paired tag. The notification can include a new location of the paired tag.

Abstract: A method and apparatus for facilitating audio communication remotely with a person includes the use of several observation devices, each having an audio system that can play audio signals and receive acoustic signals and convert them to audio signals. The audio signals are wirelessly communicated in the region via a wireless local area network, and outside of the region by a wide area network via a gateway device. The audio signals from a command console located remotely from the region are playing in a synchronizations by several of the observation devices such that the resulting acoustic signals combine additively at the location of a person in the region with whom communication is conducted. The observation devices are designed to be deployed on an ad hoc basis to facilitate rapid deployment of the system.

Abstract: A system of an alert puck, a mobile communication device, and an alert server for facilitating a VOIP session with the mobile communication device responsive to an emergency event triggered by the alert puck. The alert puck comprises a housing enclosing a sealed volume, a power supply and control circuitry that includes a personal area network (PAN) interface. The mobile communication device comprises an operating system, an alert application executing upon the operating system, and a wireless transceiver. The alert server contacts a set of one or more previously defined contact devices, conveys an emergency message, and facilitates the VOIP session with the alert application, when a button is pressed on the alert puck.