Real Time Locating Systems (RTLS) are electronic systems that are intended to locate small electronic devices on people or things at any time. None are perfect in this respect but to qualify for the term, they must give real time identity and location most of the time, or when interrogated. There are many situations calling for RTLS, particularly now that it has become affordable and the mobile devices that are sensed have, in many cases, become small and convenient. Let us look at some examples.
Hospital staff have traditionally had difficulty summoning assistance when faced with an emergency medical situation or, increasingly, physical assault. Alarm pendants have alerted backup but not given position. Timely location of a child lost in a theme park and possibly in danger has been impractical. Supply chains are traditionally tracked by RFID, barcodes and so on with a similar lack of precision. At best one knows that the package or conveyance passed a choke point at some stage and heroic assumptions are then made as to where it now resides. Vehicles are also tracked with imprecision. Postal services need to "switch the light on" and take a holistic automated approach. The antidote to these and other shortcomings is RTLS.
RTLS has consisted of very short range infra-red systems and complex, multiple antenna, multiple beam long range RFID, making it an esoteric niche market with only 900 such systems having been sold to date. However, with the new portability and affordability of RTLS in various forms, its use is now increasing sharply to become a $2.71 billion business in 2016. New principles are being brought to bear, such as parasitic and therefore economical WiFi locators and zonal RFID (arrays of interrogators in, say ceilings of buildings, so the "tag" is never out of range).
Some of the largest companies in the world are now active in RTLS, which will become 40% of the active RFID market in only ten years. These companies include Mitsubishi, Cisco, IBM, Microsoft and Motorola. They know that this is not like the highest volume uses of passive RFID tags where disposable labels are usually involved and the label cost can be 50% of total cost. RTLS is more of a systems business as shown in the IDTechEx forecast of the share of spend in 2016 given below.
Share of spend on RTLS in 2016 in millions of dollars
Source: IDTechEx report Real Time Locating Systems (RTLS) 2006-2016.
The number of companies supplying all or part of the RTLS value chain is growing rapidly as shown below, lending credibility to the forecasts.
Trend in number of significant suppliers into parts of the RTLS value chain 2006, 2010 and 2016
Source: IDTechEx report Real Time Locating Systems (RTLS) 2006-2016.
Uniquely, the new report Real Time Locating Systems (RTLS) 2006-2016 by IDTechEx brings the subject to life with no less than 41 case studies of RTLS in action today and 20 supplier studies.
There is a thorough consideration of the extension of the technological repertoire that will underpin the rapid adoption of RTLS in future. An example is the promising, but little used principle of measuring the angle and attenuation of a single returning beam, known as Received Signal Strength Indication RSSI. That could even make RTLS a consumer product. Find your lost child, track where your cat goes at night...
The IDTechEx analysts also consider radio fingerprinting, mesh networks and linking GPS, GSM and other positioning in a tiny active RFID device to enable it to be located in real time, not used for navigation. Standards, privacy issues and impediments to rollout of RTLS are also considered.
Today, most RTLS operates in the license free frequency range 300-433.92 MHz but there is a strong trend to dominance of 2.45 GHz in future, particularly because of Time of Flight active RFID is efficient at that frequency and because the new RTLS based on WiFi, Bluetooth and ZigBee uses that frequency. Long range passive Surface Acoustic Wave (SAW) tags will also provide RTLS at 2.45 GHz. UHF around 900 MHz will also be used and dual frequencies will increasingly be popular. The signpost system by which long range tags are woken up by short range signposts will become more common.
The main applications of RTLS will be in manufacturing, military, healthcare, postal/ courier, research and development and military sectors but with increased interest from most other sectors including retail and agricultural.
For more read the brand new IDTechEx market report Real Time Locating Systems (RTLS) 2006-2016. This unique report covers the technology and market for what will be a multi-billion dollar market by 2013. It includes active RFID devices based on WiFi, etc, and over 60 case studies. Go to www.idtechex.com 
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