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RTLS and Wireless Technologies

Monitoring the Convergence of RTLS and Enabling Wireless Technologies
(Courtesy: Venture Development Corporation)

The promises of Radio Frequency Identification (RFID) have excited the imagination, yet there have been few viable solutions that can provide extensible, wide area coverage with 100% read rates and precision location of assets and personnel. Enter Real-Time Location Systems (RTLS) and, more importantly, the convergence of RTLS with other wireless technologies (i.e., 802.11 WLAN, Wi-Fi, GPS, UWB).

Real-Time Location Systems (RTLS) are systems based upon the use of active RFID tag technology and use the transmissions from the active tag as seen by several readers to accurately triangulate the position of the tag using amplitude, time-of-flight, or differential time-of-flight information.

RTLS solutions move beyond the typical restrictions of RFID systems in terms of providing precise location information. These systems provide coordinate-based information on where the RTLS tag is located, allowing the tag's location to be precisely mapped and compared to other tags and its surroundings.

In addition, RTLS systems are more complex than RFID systems. A typical RTLS tag is battery-powered and communicates with not one but several different receiving devices. Each received message will arrive at a slightly different time and at a different RF signal strength. RTLS solutions have long range communication of 50 to 100 meters, with the ability to locate tags to within 10 feet.

RTLS applications have become of extreme interest for many users because of the wide range of problems that can be solved with the unique combination of wireless technologies. For example: - Pallets or containers are often stored in the wrong location in a large warehouse or yard and cannot be located on demand;

  • Expensive tools or parts cannot be found when needed, slowing production. More are purchased and asset utilization drops as capital expenditures rise;
  • Critical work-in-process cannot be located among scores of similar-looking items;
  • High-security facilities have no knowledge of personnel movements after people clear security checkpoints; and
  • Enterprises have thousands of high-value mobile assets, with theft and inefficiency as primary challenges to address. As the RTLS market continues to take shape, the growth of RTLS from being a niche solution to becoming an enterprise application is being powered by the increasing number of WLAN, Wi-Fi, GPS, and UWB deployments in diverse fields such as manufacturing, logistics, retail, hospitality, defense, etc. Here VDC will explore these enabling wireless technologies and their convergence with RTLS.

    I. RTLS and WLAN - VDC expects RTLS to play a significant role in shaping the WLAN landscape. These wireless solutions focus on ushering in enterprise applications that spawn efficiency, profitability and growth for its adopters. The IEEE 802.11 standard was developed for high-speed data communications. The architecture was designed to operate at data rates of a minimum of 1Mbps. Communication at these data rates over ranges of hundreds of feet requires approximately 100mW of power. Therefore, these radios are normally installed in devices that have rechargeable batteries.

    In addition, locatable tags must remain operable for years in order to be maintenance free and cost effective. Consequently, the data rates of these tags are much slower, trading data rate for range, while still requiring only very low power transmissions from the tags. WLAN-based RTLS offerings are increasing their presence in the market, driven by demand from users hoping to leverage existing 802.11 systems.

    II. RTLS and Wi-Fi - The RTLS market will also be a key beneficiary of the enterprise Wi-Fi adoption trend. VDC expects national security initiatives to accelerate adoption in government and logistics/distribution markets in North America and EMEA. However, individual privacy concerns may stall human asset tracking in European markets and union-represented industries.

    Furthermore, enterprises with Wi-Fi deployed will likely have faster adoption rates and sales cycles of less than 6 months as customer success stories are communicated and vendors and systems integrators build implementation competencies. And, where customers lack Wi-Fi networks for build out and RTLS, one should expect 6- to 9-month sales cycles to move from trial to wider deployment.

    RTLS solutions can enable enterprises across multiple industries to take advantage of existing WLAN and Wi-Fi networks to locate and manage high-value assets easily and at a lower total cost of ownership. This delivers increased asset utilization, streamlined operations, and improved productivity, all resulting in tangible and rapid ROI.

    III. RTLS and GPS - Global Positioning Systems, or GPS, is a type of RTLS technology, very useful for tracking vehicles. But GPS is not appropriate technology for tracking hundreds or thousands of tags in a fixed space, especially indoors. GPS-based tracking applications are mostly limited to vehicles that have a need for a cell phone, and are integrated with the cell phone.

    Despite extraordinary advances in GPS technology, millions of square meters of indoor space are out of reach of GPS satellites. Their signals, originating high above the earth, are not designed to penetrate most construction materials. So the greater part of the world's commerce - which is conducted indoors - cannot be tracked by GPS.

    Even for outdoor applications, GPS does not provide the accuracy of location that is possible with RTLS. Some of these systems are capable of providing asset location accurate to a radius of 10 feet. GPS systems are not capable of providing this level of accuracy.

    Additionally, GPS does not provide a cost-effective way to track thousands of assets. GPS chips are highly complex and require a substantial power source for operation. And, although GPS can determine its own location, a second radio system is needed to report this location to a central computer.

    Some embedded GPS systems can also be considered RTLS systems. In these systems, a tag uses the GPS satellite network to locate itself using latitude, longitude, and elevation. If the tag then sends this information on to the rest of the system in real time (i.e. through a wireless radio link, similar to active RFID); then the GPS system is operating in RTLS mode. GPS-enabled RTLS solutions are expected to remain niche-oriented, with users managing large vehicle fleets serving as early adopters.

    IV. RTLS and Ultrawide Band (UWB) - The term "ultrawide band" refers to the development, transmission and reception of extremely short duration bursts of radio frequency (RF) energy - typically ranging from a few hundred picoseconds (trillionths of a second) to a few nanoseconds (billionths of a second) in duration. UWB technology supports read ranges in excess of 200 meters (650 feet), resolution and accuracies of better than 30 cm (1 foot), battery lifetimes in excess of 5 years, fewer tag components (i.e., 25 versus 150), and micro-miniature tag sizes.

    For RTLS applications, UWB further translates into superb performance and robust operation in severe multi-path environments (i.e., within most industrial and hospital applications). Multi-path, or "multi-path cancellation" occurs when a strong reflected wave - e.g., off of a wall, file cabinet, ceiling, vehicle, building, etc. - arrives partially or totally out of phase with the direct path signal, causing a reduced amplitude response at the receiver. With very short pulses, the direct path has essentially come and gone before the reflected path arrives and no cancellation occurs.

    UWB systems are approved for unlicensed use within the United States under FCC Part 15, specifically Subpart F and Part 15.250, permitting both indoor and outdoor use. The FCC Part 15.250 band spans from 5.925-7.250 GHz. European regulators are currently considering the authorization of UWB-based RFID and RTLS systems within the 6.0-9.0 GHz, overlapping allocations within the U.S.

    As a market, VDC expects RTLS to reach an estimated $55 million in 2005, with rapid growth (37.5% compounded annually) anticipated through 2008. Although this forecast is conservative, there is tremendous growth opportunity if the industry works on growing the available market and leveraging enabling wireless technologies.

    RTLS and its convergence with existing wireless technologies discussed here are currently under investigation by VDC as part of its 2005-2006 RFID Business Planning Service. To view the program proposal, go to:

    About VDC
    Venture Development Corporation (VDC) is an independent technology market research and strategy consulting firm that specializes in a number of retail automation, RFID, AIDC, embedded, component, industrial, and defense markets. VDC has been operating since 1971, when the firm was founded by graduates of the Harvard Business School and Massachusetts Institute of Technology. Today, we employ a talented collection of analysts and consultants who offer a rare combination of expertise in the market research process; experience in technology product and program management; and formal training in engineering and marketing. VDC's clients include thousands of the largest and fastest-growing tech suppliers in the world and the most successful investors participating in the markets we cover.

    For further information about the "RFID Business Planning Service 2005-2006: Global Asset and Transaction Management Systems Market Analysis" or any other VDC service, contact:

    Marc Regberg, Vice President, 508-653-9000 ext. 111,