Radio-frequency identification. Radio-frequency identification (RFID) is the wireless use of electromagnetic fields to transfer data, for the purposes of automatically identifying and tracking tags attached to objects. The tags contain electronically stored information. Some tags are powered by electromagnetic induction from magnetic fields produced near the reader.
Some types collect energy from the interrogating radio waves and act as a passive transponder. Other types have a local power source such as a battery and may operate at hundreds of meters from the reader. Unlike a barcode, the tag does not necessarily need to be within line of sight of the reader and may be embedded in the tracked object. RFID is one method for Automatic Identification and Data Capture (AIDC).[1] In 2014, the world RFID market is worth US$8.89 billion, up from US$7.77 billion in 2013 and US$6.96 billion in 2012. History[edit] Design[edit] Tags[edit] RFID tags can be either passive, active or battery-assisted passive. Readers[edit] Uses[edit] Near-field electromagnetic ranging. Near-field electromagnetic ranging (NFER) refers to any radio technology employing the near-field properties of radio waves as a Real Time Location System (RTLS). Overview[edit] Near-field electromagnetic ranging is an emerging RTLS technology that employs transmitter tags and one or more receiving units.
Operating within a half-wavelength of a receiver, transmitter tags must use relatively low frequencies (less than 30 MHz) to achieve significant ranging. Depending on the choice of frequency, NFER has the potential for range resolution of 30 cm (1 ft) and ranges up to 300 m (1,000 ft).[1] Technical Discussion[edit] Advantages[edit] NFER technology is a different approach for locating systems.
For instance, a radio wave at 1 MHz has a period of 1 µs, and the EH phase difference changes about 45 degrees between 30 m (100 ft) to 60 m (200 ft). Using relatively low frequencies also conveys additional advantages. Disadvantages[edit] Operation at low frequencies faces challenges as well. Real-time locating system. 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.[1] 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. Origin[edit] Indoor Autonomous Positioning. SCP technology makes it possible to provide reliable, consistent, and accurate indoor positioning without the support of network infrastructure and services.
By exploiting freely available signals including GPS, cellular, digital television, and wireless LAN (e.g. WiFi), SCP based Doppler Aided Inertial Navigation (DAIN) determines location through a sensor fusion approach. Combining inertial, magnetic, and gravity data with the SCP RF observables, DAIN provides continuous position, velocity, and direction information. A fundamental breakthrough in indoor positioning, SCP DAIN is ideal for emerging location enabled applications hosted on smart phone devices. The technology delivers unprecedented performance in a cost-effective, software-based solution. SCP DAIN is a compelling augmentation to outdoor GPS, delivering GPS-like accuracy indoors.
DAIN is an ideal enabler for both consumer and commercial applications. The Institute of Navigation. MSI_Whitepaper. Indoor Navigation with SVG. SVG, positioning technologies, mobility, guiding system Christian SchmittResearcherFraunhofer FIT Schloss Birlinghoven Sankt-Augustin Germany christian.schmitt@fit.fraunhofer.de Oliver KaufmannFraunhofer FITSchloss Birlinghoven Sankt-Augustin Germany oliver.kaufmann@fit.fraunhofer.de This paper describes a mobile guide providing office building visitors with indoor navigation aid. The guide is implementing using a combination of several indoor positioning systems and a SVG-based map viewer for an interactive map visualisation.
A combination of several positioning systems is necessary because there is no single technology that can satisfy the system requirements with regard to accuracy and costs. 1. 1. FIT has a long history in developing mobile guides for museums, fairs, symposiums. Our mobile guide was developed with the aim to be used for demo purposes by visitors to our institute, for demonstrating our expertise in mobile computing, positioning technologies and human-computer interface.