An article to be surveilled includes an article body and an electronic article surveillance (EAS) tag. The EAS tag is attached to, preferably integrated into the article body. The tag includes a power source, a processing device in electrical communication with the a power source, and at least one piezoelectric element in electrical communication with the processing device. The processing device is operative under certain conditions to use power from the power source to generate a signal causing the at least one piezoelectric element to emit ultrasound energy in a pattern based on the signal. In some examples, the tag, transmitting an ultrasound signal emitted by the piezoelectric element is detected by a reader of the EAS system. The EAS system determines whether the detected signal meets an alarm condition; and upon such determining, indicates, an alarm.

Tracking tags for attachment to an object or animal. The tracking tags may include low-power long-range transmitters drawing power from a battery or a renewable energy source. The tracking tags may also each include a microcontroller having a sleep-mode module enabling nearly no quiescent current to be drawn when the microcontroller is in a sleep-mode. The microcontroller may enter into a sleep-mode for long periods of time following a short period of sending data to the low-power long-range transmitter. The short period of sending data may be approximately one-twentieth of the long sleep-mode period. The tracking tags may also include sensors for determining an ambient temperature or biometric data about an animal to which the tracking tag is attached. Locations of the tracking tags may be determined using signal trilateration and/or signal triangulation.

Disclosed is tagged ammunition, methods for making it, using it and detecting it to reduce gun violence. When implemented together with a smart phone coupled readers, standalone readers, or at a security center, software is included to allow integration of signals detected by multiple readers in the vicinity to map detectable ammunition detected by readers designed to detect tagged ammunition as a proxy for loaded firearms. This makes possible securing an area of interest, when combined with placing of at least one networkable reader in the vicinity of the area of interest; and connecting the one or more readers to a monitoring center. Such monitoring centers may be associated with schools, shopping malls, streets, public meetings, public events, housing complexes, an area being swept for loaded guns, an area being monitored for gang activity, or even a residence.

The described payment device includes an integrated power source including a piezoelectric accelerometer. Upon motion of the payment device, kinetic energy may be translated to a mass of the piezoelectric accelerometer to generate electrical energy to power other functions of the payment device. Motion translated to the piezoelectric accelerometer may also be used in combination with other inputs to implement security functions of the payment device.

Systems and methods for operating an RFID transponder (102). The methods involve: performing energy harvesting operations by a voltage scavenging device (130) of the RFID transponder to collect energy from an RF field, magnetic field, heat, light or movement of the RFID transponder; increasing or decreasing, by a voltage converter of the RFID transponder, a voltage level of a signal received from the voltage scavenging device to a sub-threshold voltage level that is at least one order of magnitude below a normal operating range for the RFID transponder; and supplying an operating voltage at the sub-threshold voltage level to at least a transceiver circuit (124) of the RFID transponder.

Disclosed is tagged ammunition, methods for making it, using it and detecting it to reduce gun violence. When implemented together with a smart phone coupled readers, standalone readers, or at a security center, software is included to allow integration of signals detected by multiple readers in the vicinity to map detectable ammunition detected by readers designed to detect tagged ammunition as a proxy for loaded firearms. This makes possible securing an area of interest, when combined with placing of at least one networkable reader in the vicinity of the area of interest; and connecting the one or more readers to a monitoring center. Such monitoring centers may be associated with schools, shopping malls, streets, public meetings, public events, housing complexes, an area being swept for loaded guns, an area being monitored for gang activity, or even a residence.

Tracking tags for attachment to an object or animal. The tracking tags may include low-power long-range transmitters drawing power from a battery or a renewable energy source. The tracking tags may also each include a microcontroller having a sleep-mode module enabling nearly no quiescent current to be drawn when the microcontroller is in a sleep-mode. The microcontroller may enter into a sleep-mode for long periods of time following a short period of sending data to the low-power long-range transmitter. The short period of sending data may be approximately one-twentieth of the long sleep-mode period. The tracking tags may also include sensors for determining an ambient temperature or biometric data about an animal to which the tracking tag is attached. Locations of the tracking tags may be determined using signal trilateration and/or signal triangulation.