Chapter1.Technology Overview

Chapter 1. Technology Overview

Radio frequency identification (RFID) technology uses radio waves to automatically identify physical objects (either living beings or inanimate items). Therefore, the range of objects identifiable using RFID includes virtually everything on this planet (and beyond). Thus, RFID is an example of automatic identification (Auto-ID) technology by which a physical object can be identified automatically. Other examples of Auto-ID include bar code, biometric (for example, using fingerprint and retina scan), voice identification, and optical character recognition (OCR) systems.

Consider the word identify more closely. Although two cans, A and B, of a particular brand of motor oil in a store might look identical, substantial differences between the two might in fact exist. For example,

• The retailer might have used two different order numbers to obtain cans A and B from the distributor.

• Can A might have been produced in North America, whereas can B might have been manufactured in Asia.

• A person named Bob might have loaded A onto the delivery truck, whereas a person named Chi might have loaded B onto a similar truck.

• Can A might have arrived in the store on a different date than when can B arrived.

Generally, although none of the preceding information appears on cans A or B for a person to view in a store, this information is nonetheless associated with these cans. You can, by using a set of such information, uniquely identify can A from can B. Also, even assuming that no such information exists, the very fact that that two distinct physical objects exist suggests the possibility to distinguish them (for example, by assigning a number that is unique to can A and one that is unique to can B). In summary, although cans A and B might look identical in appearance, composition, expiration date, recycling information, and so on, they can actually be differentiated in some way so that cans A and B, and any other can of motor oil produced by this particular manufacturer (or any other manufacturer), are unique in some way. When used in the context of RFID, the word identify refers to this uniqueness of an object.

The implications regarding object identity are tremendous. For example, consider how the preceding example of motor oil can be extended to other objects, irrespective of whether RFID technology can be used with:

• Every grain of rice consumed annually worldwide

• Every grain of sand on every beach worldwide

• Every leaf on every tree worldwide

• Every drop of rain that falls worldwide in a given year

The objects in this preceding list represent potential identification scenarios. Current RFID technology cannot be used to identify these objects. Even with technological advances (over the next 10 years, for example), some (or all) of these identification scenarios are unlikely. After all, how can you tag a raindrop, which has an extremely short life and dynamic behavior (such as dividing into smaller raindrops when it grows beyond 5 mm in size)?

Before delving into a detailed discussion of RFID technology, you need to understand the fundamental terms and concepts associated with RFID. The following section serves as an RFID technology primer.