Aeroscout Ltd.

Other

Reuven Amsalem

Daniel Aljadeff

Amir Lavi

Alexey Kalmanovich

Adi Shamir

Yair Granot

Shalom Tsruya

Gabi Daniely

Jonathan Chashper

Niv Raz

A radio frequency portable tag for a location system comprises a transceiver configured to send and receive radio frequency location and communication signals, an activation signal receiver configured to receive activation signals to activate the tag and/or the transceiver, and an activation signal transmitter configured to send activation signals for activating other radio frequency tags.

Radio frequency portable tag for location system

A wearable electronic device assembly has a strap attached to the device for attaching the device to a wearer, and a connector for securing two overlapping end regions of the strap together. The connector has first and second parts configured to be secured together with the two overlapping end regions of the strap extending between them, to secure the two end regions together. The first part has a projection arranged to extend through or adjacent to the strap. The second part has a main body having an aperture to receive the projection of the first part, and a securement part movable with respect to the main body between a released position and a securement position. The projection is retained in the aperture to secure the first part of the connector to the second part of the connector.

Wearable electronic device assembly

A wireless network has at least one wireless unit which transmits messages in multiple channels. The messages are synchronously transmitted using a transmit clock signal. The at least one wireless unit starting transmission of the messages at intervals consisting of at least one of one or multiple periods of the transmit clock signal. A plurality of location receivers are used for receiving the messages at different channels transmitted by the wireless units within the wireless network and determining a time of arrival for the received messages. At least one master unit is used for receiving the time of arrival from each of the location units. The location of the wireless unit is to be determined on the Time Difference Of Arrival (TDOA) of the transmitted messages at the location units.

Multi-channel TDOA system

A wireless location system has at least one wireless tag to be located by the wireless location system, wherein the at least one wireless tag transmits two wireless signals having a known time relationship and having different bandwidths. A plurality of receivers is provided wherein a first receiver receives and processes a first of the two wireless signals and estimates a time to arrive (TOA) of the first wireless signal, and a second receiver receives and processes a second of the two wireless signals and estimates a TOA of the second wireless signal at the second transceiver. The plurality of receivers is time synchronized based on a common timing signal. A location server is coupled to each of the plurality of receivers. The location server receives the TOA of the first wireless signal from the first receiver and the TOA of the second wireless signal from the second receiver. The location server calculating a TDOA of the two wireless signals and estimates a position of the at least one wireless tag based on the TDOA.

Dual bandwidth time difference of arrival (TDOA) system

A method for reducing synchronization offset errors in a TDOA location finding wireless system, comprising: receiving transmissions from at least one sync unit at multiple location transceivers, wherein the multiple location transceivers are synchronized from the sync unit; determining actual times-of-arrival of the received transmissions in response to receiving transmissions; performing a wireless distance measurement between the transceivers and the at least one sync unit, the wireless distance measurement performed by the transceivers in response to the received transmissions from the at least one sync unit; computing an actual propagation time between the sync unit to the transceivers; computing differences between the actual propagation time and theoretical propagation time determined in conformity with the predetermined locations; estimating synchronization offset error of the transceivers in conformity with the computed differences; and correcting the synchronization offset error.

Method and system for synchronization offset reduction in a TDOA location system

A wireless local area network (WLAN) method and system for presence detection provide a low-cost and WLAN-compatible means for detecting the presence of an asset without requiring full location-finding support within a WLAN environment. The presence of a transmitter is detected by examining the signal strength of a presence signal. The presence signal is WLAN-compatible, but does not require association of the transmitter with the WLAN and does not require a response from the WLAN. The presence signal may be transmitted on multiple WLAN channels for presence detection by multiple WLAN APs. The presence signals transmissions may be periodic or may be stimulated by a stimulus from the WLAN or external device that may or may not be coupled to the WLAN. Location finding can also be performed in combination with the signal strength presence detection.

Wireless local area network (WLAN) method and system for presence detection and location finding

A system and method for tracking and locating wireless tags by a wireless location system in limited and well defined areas that provides for differentiation between the well defined areas comprises transmitting identifying area information by short range transmitters, at least one short range transmitter positioned in the proximity of an entry and exit point of each well defined area. The wireless tags receive the identifying area information when in coverage range of one of the short range transmitters. The wireless tags will transmit the identifying information in the tag message. The transmission will include the last identifying information received and accepted by the wireless tag. A plurality of location receivers and/or access points are installed in or in the proximity of the well defined areas for locating the wireless tags.

Enhanced area separation in wireless location systems and method

A radio-frequency identification (RFID) tag employing a unique reception window and method for operating the tag system provides low-power operation for enhanced tag battery life, while providing addressable tags that can receive commands and data from the system, which can be a wireless local area network (WLAN) incorporating location finding for locating the tags. Interference with other tags and other transmitters is prevented by either using a sniffer circuit to determine that no network transmission is in progress, or by using a special non-interfering coding sequence. A receiver within the tag is operated for a predetermined period of time after a periodic transmission is made from the tag, and an address decoder determines if the tag is being addressed. The receiver can receive data and/or commands after being addressed and is shutdown if the window time elapses, the tag is not addressed, or at the completion of data/command transfer.

Radio-frequency identification (RFID) tag employing unique reception window and method therefor

A wireless local area network (WLAN) radio-frequency identification (RFID) tag system provides location finding in a wireless local area network (WLAN), using a WLAN channel. Interference with the WLAN is prevented by either using a sniffer circuit to determine that no network transmission is in progress, using a modified coding sequence or preamble to cause standard WLAN receivers to ignore the RFID tag transmissions, or transmitting a message using a standard WLAN signal addressed to an address not corresponding to a unit within the WLAN. Location units (LUs) and a master unit (MU) within the WLAN receive the RFID tag transmissions and can determine the location of a tag by triangulation based on differences between the signals received at the location units from the tag. The master unit receives the signal information from the location units and computes the location of the tag. Time-difference-of-Arrival (TDOA), received signal strength indication (RSSI) or other triangulation techniques may be used.

Growing community of inventors

Nes-Ziona, Israel

Reuven Amsalem