I n t r o d u c t i o n
Radio frequency identification (RFID) has evolved into a reliable, cost-effective technology used for personal identification, asset management, security, shipping and receiving, inventory control, and many other perations. Improved performance, falling prices, and developing standards continue to move RFID into the mainstream and have made it practical for many organizations to consider its use. This white paper will help you determine if RFID is right for your organization. It describes how RFID works and how it is used, and provides tips for starting an RFID project.
What Is RFID and How Does It Work?
RFID is an identification technology that uses wireless readers to access data encoded in chips. The chip is mounted to an antenna, which receives RF signals from the read/write device. The basic form of a chip attached to an antenna is called a transponder or tag. An inlay is created by mounting the tag on a substrate. The inlay can then be layered into or attached to a label or other form factor, such as a wristband, and the result is referred to as smart media. The smart media can then be attached to an object and carry all kinds of data about that object.
Most inlays used today are passive, which means they are powered up by the read/write device and do not have their own power source. Active RFID technology includes a power sourceusually a long-life batteryfor the tag to power data transmission to the reader. Active tags provide much more range than passive tags, but are also bulkier and more expensive.
Data is written to and read from an inlay with an RFID reader/encoder, also called an interrogator. The reader/encoder creates an RF energy field at a specific frequency. Passive inlays receive the reader signal through their antenna, which wakes them up and allows them to broadcast data. All inlays within the energy field automatically respond to the reader, which accepts and decodes the data. Many tags are rewritable and most readers can also encode. Specialized middleware is used to manage the flow of and hierarchy of the data as it is transmitted from reader/encoders into the information system.
RFID tags are also rewritable. Data can be added or updated throughout the life of the tag, which makes the technology suitable for creating a pedigree to associate with an object throughout its useful lifecycle. Tags can also be reused by erasing them and encoding new data.
The EPC UHF Gen 2 protocol was created specifically to meet RFID user needs for traceability and supply chain operations. It has been widely accepted by government agencies, retailers, logistics providers, and manufacturers, and particularly in the consumer goods, retail, pharmaceutical, and defense industries. Best Buy, Target, the U.S. Department of Defense (DoD), and Wal-Mart are among the organizations that have specified Gen 2 for their compliance tagging programs. Following is a brief outline of the EPC standard and the body that oversees developments.
The EPC System
The Electronic Product Code (EPC) system is developed and administered by EPCglobal Inc. The complete EPC system includes technical specifications for interoperable tags and equipment, a numbering system to categorize and uniquely identify billions of items, plus database and network services to help organizations process and share EPC data. As a joint venture between GS1 (formerly know as EAN International) and GS1 US (formerly the Uniform Code Council, Inc.), EPCglobal leverages a nearly 30-year heritage of successfully partnering with industry. EPCglobal is a neutral, consensus-based, not-for-profit standards organization.
The EPC number is used to uniquely identify an item and convey its manufacturer and product type. The latest EPC standard, Gen 2, specifies a 96-bit EPC identifier. The number is divided into four sections: header, manager number, object class, and serial number. The header identifies the length, type, structure, version, and generation of EPC, so equipment and software applications can accurately process the information that follows. The manager number identifies the company or entity that assigned the EPC number. The object class categorizes the object, similar to a stock keeping unit (SKU). The serial number is what sets EPC numbers apart from U.P.C./EAN and other numbering systems. The serial number uniquely identifies the item within the object class.
The EPC system was designed to facilitate supply chain operations and object tracking by multiple organizations. EPC Discovery Services and the EPC Information Service (EPC IS) facilitate information exchange.
EPC Discovery Services help users locate and access data related to specific EPC numbers. Object Naming Service (ONS) is a Discovery Services component that provides a network address to where actual data for a specific EPC is held.
EPC Information Services let organizations exchange data about specific EPCs through the EPCglobal Network, a collection of technologies and components for identification and data sharing. Companies that assign EPC numbers can maintain EPC IS servers with item information. Using EPC numbers does not require organizations to share EPC data or use other components of the system. Visit www.epcglobalinc.org for more details about the EPC system and technologies.
There are EPC specifications for UHF and high-frequency technology, and passive and active tags. By far the most activity, interest, and product commercialization has been for passive UHF technology, especially the EPC Generation 2 (Gen 2) UHF standard.
The characteristics described above apply to most RFID systems. There are many variations of RFID tags or inlays which work essentially the same way but have major differences in their read range, speed, chip memory, security, resistance to interference, physical construction, and other characteristics.
Frequency is one of the biggest and most important differentiators. RFID systems are available at many frequencies. RFID technologies most commonly used in commercial applications operate in either the 860960 MHz ultrahigh frequency (UHF) band, or at 13.56 MHz, which is classified as high frequency (HF). High frequency RFID is usually used for short-range (less than 24 inches) applications such as access control, ticketing/fare collection, and some item tracking and electronic shelf-management applications. UHF technology has an upward range of around 20 feet and is used for shipping and receiving, production control, material handling, and many other industrial and supply chain operations. There are numerous technical and industry standards for both UHF and HF RFID.
RFID is highly advantageous for asset management applications because tags can provide a durable, permanent identifier, with extra memory that can be updated repeatedly with configuration settings, inspection records, service information, and other dynamic information. RFID asset tagging also facilitates efficient audits and inventories because assets can be detected and recorded at a distance, without requiring a worker to manually read and record information from the asset tag. Asset movements can be tracked and recorded automatically with RFID reading portals, which can be programmed to issue alerts if assets are removed from the area. Logistics assets represent another excellent opportunity to benefit from RFID. Many returnable containers are never brought back from customer sites after shipment, forcing companies to carry excess inventory to ensure adequate supplies of shipping materials where they are needed. Almost half of the respondents to an Aberdeen Consulting study reported that logistics asset opoerations consume 5 percent or more of corporate revenue.
Twenty-five percent of companies say they lose in excess of a tenth of their container fleet each year. Identifying returnable containers with smart labels or fixed tags enables companies to augment their legacy bar code shipping applications by automatically recording materials shipped to customers. Companies can then find their own pallets in shipping yards or docks stacked with thousands of items belonging to dozens of companies. Higher degrees of tracking will enable organizations to lower their material costs and will provide an audit trail that can be used to bill customers if materials are not returned. The value of these applications has been proven in multiple real-world implementations.
Many large libraries around the world have implemented RFID to speed material check-in, checkout, shelf inventory, and security applications. Low-cost, flexible smart labels are inserted in books and can be made invisible to patrons. Counter personnel check dozens of books in or out in mere seconds without manually handling and orienting each item. The tags can also be used for theft detection, much like anti-shoplifting technology currently used by retailers. Librarians using portable computers with RFID readers can take inventory and find misfiled materials simply by walking down an aisle of bookshelves. The reader can automatically detect missing materials and alert the operator.
Video rental stores use RFID for similar applications. Readers are positioned at the checkout, unattended return bins, and doorways to record transactions and detect shoplifted items automatically. These library and video store operations are essentially in-store inventory management applications that can be adapted for use in many other industries. The application can also be adapted to manage tool crib operations, evidence management, file tracking, and other check-in/checkout applications.
A smart label can provide secure, lifetime tracking that can facilitate accurate warranty and returns authorization and anti-counterfeiting protection. In 2004 the U.S. Food and Drug Administration (FDA) Anti-Counterfeiting Task Force recommended wide-scale adoption of RFID to stop counterfeiting, which now affects between 6 percent and 10 percent of all pharmaceuticals worldwide. The task force report, which earned widespread industry support, singles out RFID as the most promising tool to combat counterfeiting. For more information about how RFID can be used to protect pharmaceuticals, see Zebras white paper Track and Trace Solutions for the Life Sciences Supply Chain. RFID systems and business processes to prevent counterfeiting, provide brand protection, and improve channel integrity can be adopted for use in many industries. Zebras white paper Brand Protection in the Supply Chain: Protecting Products and Profits with Secure Media Solutions describes these applications in more detail.
Access Control, Personal Security, and Patron Management
Personal identification is a longtime and very widespread application for RFID. Tags embedded in employee ID cards provide hands-free access to secured buildings and a tamper-proof form of identification that ensures only authorized personnel are admitted. Similar systems are used to identify hospital patients and patrons at theme parks, where the ID card or RFID wristband is also used as part of a cashless payment system.
Cashless payment is an effective retail application unrelated to item or shipping container tagging. The most widespread example of RFID cashless payment is ExxonMobils Speedpass program, which is saving millions of drivers countless hours at the pump.When the tag enters the reader field at a gas pump, it turns on the pump and automatically charges the gas purchase to the drivers registered credit card account, promoting quicker service while maintaining complete account number confidentiality. McDonalds restaurants are now offering a similar application to speed transactions at the counter and drive-thru window.
RFID-based cashless payment is also used for electronic toll collection applications in use on toll roads and bridges. Participating drivers have either a passive tag, which is clipped to their key chain, or a battery-powered active tag attached to the vehicle. Drivers receive their tags after subscribing to the program and depositing money into an account. The fare is deducted from the tag automatically whenever the vehicle passes through the toll gate. Drivers dont need to stop, or even slow down in some cases, to pay the toll.
Launching RFID in Business Operations
The applications described above only scratch the surface of how RFID can be used, and there are many more applications possible. Regardless of the application, there are several steps you can take to help your RFID project be productive and successful. One of the most important issues to consider is where and how to begin. As youve seen, RFID has characteristics quite unlike other technologies, and can be difficult to implement for the uninitiated. Determining how best to harness RFIDs capabilities is one of the first challenges project managers face. Zebra is a pioneer in RFID smart label technology and applications.Weve been involved in numerous projects and gained valuable insight into the questions that organizations face and the information they need, which we share in the following sections. Examining the questions and guidelines that follow will help build a strong foundation for your RFID efforts.
Determine the Business Benefits
Companies who already have some form of auto-IDsuch as bar codesfor business processes can reap strong benefits by selectively using RFID to enhance operations. For example, making only a small, incremental improvement to shipping accuracy can produce strong benefits, as the following calculation illustrates. Various analyses have established that shipping errors cost between $60 and $250 to resolve, depending on labor rates, shipping expenses, and the amount of clerical and administrative time required. Therefore, each one percent improvement in shipment accuracy should reduce shipping expenses between $60 and $250 per every 100 shipments. For a company that ships 100 orders a day, each one percent improvement in shipment accuracy would produce annual savings of $15,600 to $65,000.
Identify the Specific Business Issue That Is to Be Solved or Enhanced
For those facing compliance mandates, the issue at hand is keeping a customer that now requires RFID shipment tagging. Compliance tagging mandates set a clear requirement for what the RFID system must do. Companies that only wish to comply with customer requirements and make no other use of RFID do not need to concern themselves with considering how RFID could improve inventory, warehousing, distribution, logistics, and security. However, the most successful RFID project managers determine what other business value can be derived from leveraging the investment made to meet a compliance mandate. RFID-enabled processes can overcome environment, reliability, and throughput limitations that restrict alternative identification methods.
RFID should be used where it meets a specific need or solves a problem.
For ideas on how RFID could improve your business, review operations to determine if there are any consistent choke points or processes that require excessive human handling, such as placing items a certain side up on a conveyor. These processes are candidates to be automated with RFID, which can provide a good return on investment by reducing labor requirements and improving efficiency.
Determine What Information Is Required
Look at your business processes and limitations, and determine if things could be improved if more information was available, or if current information was available more quickly. Consider where RFID data should be collected and how often you should update related software applications.
The durability, memory, and remote reading capability of RFID tags make it practical to access information in environments where alternative technologies cant perform. In particular, the memory on RFID tags makes it possible to include information to support efficient business processes. RFID users commonly encode lot codes, expiration dates, warranty information, configuration settings, and maintenance/inspection histories that enable items to be processed or serviced when there is no access to a host database.
Identify Needed Performance Characteristics
Once data content, collection points, and communications goals have been determined it will be easier to define the performance the RFID system must provide. Application requirements drive decisions on RFID frequency, tag types, encoding method, reading equipment, and supporting software.
Test and Experiment
Pilot projects and pre-deployment testing should uncover any interference, quality, or performance problems that need to be resolved before the system is deployed. RF interference is the main concernusually produced by other wireless or RF technologies at work in the environment. An experienced RFID solutions provider can provide an assessment of potential interference and suggest remedies. The assessment is similar to the site survey that is conducted before wireless LANs are installed. Interference can be avoided or mitigated by using different styles and sizes of RFID antennas and tags, and experimenting with different frequencies, power output levels, and tag mounting options, all within the scope defined by the application requirements. Testing may not reveal every hurdle, but thorough planning can mitigate them.
Smart label printing/encoding systems should also be thoroughly evaluated. As with any labeling system, the media and adhesive must withstand all the environmental and usage conditions the label will be exposed to throughout the supply chain. It is crucial to test all the different items that will be labeled under as many conditions as possible to ensure proper performance. Because smart labels must be both encoded/write verified and printed, they can take slightly longer to produce than non-RFID labelsand in a high-speed, automated labeling environment, this must be taken into account to ensure adequate throughput.
Determine Which Standards and Regulatory Considerations Apply
There are many RFID technical standards, industry standards, and compliance guidelines, plus various national regulations for RF transmission. Companies in compliance tagging relationships will have their conformity requirements spelled out for them. Most compliance programs and other RFID initiatives in the consumer goods, retail, pharmaceutical, and defense industries specify the use of Gen 2 and other EPC standards, although there is variation among the specific requirements.
The ISO 15693 standard is prevalent for high-frequency (13.56 MHz) RFID technology. Companies who base systems on ISO 15693-standard technology benefit from a competitive vendor market that provides a choice of interoperable products. Cashless payment systems, and personal identification applications such as access control and automated time and attendance recording, frequently use ISO 15693-compatible tags and equipment.
There are other ISO and industry standards that cover a variety of RFID uses, including electronic cargo seals, logistics container identification, toll and fare collection, animal identification, and more.When considering an RFID project, check with industry associations or user groups to see if relevant RFID standards exist or are in development.
Build an Infrastructure That Can Evolve as Your Needs Change
Standards continually evolve as user needs change, new features are developed and technical limitations are overcome, and, of course, entire new standards are created. Creating a flexible RFID architecture makes it easy to manage changes. Multi-protocol RFID equipment can process tags with different specifications. For example, Zebras multi-protocol printer/encoders can encode Gen 2 chips, plus previous-generation EPC protocols and proprietary tags from several leading vendors. Multi-protocol readers can process different tags, just as most bar code scanners can auto-discriminate and recognize multiple symbologies.
RFID products built from the start to support multiple protocols are the best option. Multi-protocol readers and printer/encoders with software-defined radios (SDR) are very easy and cost-effective to upgrade. Software defined radios use software to control the RF signal modulation and demodulation and the transfer of data. Support for frequencies, standards, and options are written into the software and are not hard-wired into the hardware. Therefore, upgrades and changes are accomplished simply by downloading new software to the device. There is no need to install new components or replace the device itself. SDRs give the advantages of providing a relatively simple and expedient way to allow end users to support multiple RFID protocols and new features as they emerge.
Multi-protocol equipment with software-defined radios protects RFID investments by providing a clear and convenient upgrade path that minimizes total cost of ownership.
This paper has presented an overview of RFID capabilities and usage considerations. It may seem like a lot to learn, but remember, thousands of companies have successfully completed the RFID evaluation and implementation process, and are profiting because of it. The topics presented here provide an excellent starting point from which you can begin to identify areas for further investigation and develop specific questions to advance your project. For more information and assistance, look to RFID industry associations such as AIM Global (www.aimglobal.org) or EPCglobal (www.epcglobalinc.org), and professional societies in your specific industry. Zebra offers more white papers, implementation tips, RFID case studies, and FAQs at www.rfid.zebra.com.