Ultrasound Identification (USID)
Ultrasound Identification (USID) is a Real Time Locating System (RTLS) or Indoor Positioning System (IPS) technology used to automatically track and identify the location of objects in real time using simple, inexpensive nodes (badges/tags) attached to or embedded in objects and devices, which then transmit an ultrasound signal to communicate their location to microphone sensors. Ultrasound Identification is a real-time locating system (RTLS) or indoor positioning system (IPS) technology used to automatically determine and identify the location of objects with room accuracy. The approach is using simple, inexpensive nodes (badges/tags) attached to the surface of persons, objects and devices, which then transmit an ultrasound signal to communicate their locations to microphone sensors. Because ultrasound signal wavelengths have short reach, they are confined to lesser distant locations than with wireless transmissions with higher susceptibility to multiple reflection, multipath and through-the-wall multiple room responses. Hence ultrasound-based RTLS is considered a more robust alternative to passive radio-frequency identification (pRFID) and even to active radio-frequency identification (aRFID) in complex indoor environments (such as hospitals), where radio waves get multiply transmitted and reflected, thereby compromising the positioning accuracy. Generally the ultras
und signal does not interfere with sensitive medical equipment. A handicap of ultrasound nodes is the exposition of the sound transducer at the surface, which prevents from hermetically encapsulating the node. Vapour sterilisation is not offered with these nodes. Real-time locating systems (RTLS) are used to automatically identify and track the location of objects or people in real time, usually within a building or other contained area. Wireless RTLS tags are attached to objects or worn by people, and in most RTLS, fixed reference points receive wireless signals from tags to determine their location. Examples of real-time locating systems include tracking automobiles through an assembly line, locating pallets of merchandise in a warehouse, or finding medical equipment in a hospital. The physical layer of RTLS technology is usually some form of radio frequency (RF) communication, but some systems use optical (usually infrared) or acoustic (usually ultrasound) technology instead of or in addition to RF. Tags and fixed reference points can be transmitters, receivers, or both, resulting in numerous possible technology combinations. RTLS are a form of local positioning system, and do not usually refer to GPS, mobile phone tracking, or systems that use only passive RFID tracking. Location information usually does not include speed, direction, or spatial orientation.