Tracking objects and monitoring its movements in a large warehouse is a real nightmare for the floor supervisors. The increasing demand for location based services inside buildings have made indoor positioning a significant term.
The applications of indoor positioning are many, for instance, indoor navigation for people or robots, inventory tracking, locating patients in a hospital, guiding blind people, tracking small children or elderly individuals, location based advertising, ambient intelligence etc.
Although the Global Positioning System is the most popular outdoor positioning system, its signals are easily blocked by most construction materials making it useless for indoor positioning. indoor positioning using the Wireless Ethernet IEEE 802.11 (Wireless Fidelity, Wi-Fi) standard that has a distinct advantage of low cost over other indoor wireless technologies.
The Basic Operation of Wi-Fi positioning System is mentioned below:
• A device having Wi-Fi is attached to the object that needs to be identified.
• When the tagged object is presented in front of a suitable Wi-Fi access point (reader), the device transmits its identification data to the access point (AP).
• The AP then reads the data and has the capability to forward it over suitable communication channels.
• This application can then uses this unique data to identify the object and presents it to the aggregation and computation server software.
• The computation server performs the required location estimation algorithms and sends the output indication on the radio map.
Three Main Components of Wi-Fi positioning System:
• Tags, or transponders, affixed to objects and carry identifying data.
• Readers, or transceivers (Access Points), read/receives and interface with user-end databases.
• User-end databases, correlate data stored on tags with physical objects i.e. a host and system software.
• Contactless: A Wi-Fi tag can be read without any physical contact between the tag and the AP/reader.
• Cost Effective: Wi-Fi allows cost effective LAN deployment indoor as well as outdoor.
• Absence of line of sight: A line of sight is generally not required
• Better Security: Wi-Fi Protected Access encryption (WPA2)
• Variable range: 2.4 GHz - 5 GHz bandwidth
• Easy availability: Easily available for most new electronic devices