RFID stands for radio frequency identification. It is a technology that has existed for decades. At a simple level, it is a technology that involves tags that emit radio signals and devices called readers that pick up the signal.

RFID Technology is identified as the emerging technology in today’s AIDC industry. RFID is a data carrier therefore classified as an Automatic Data Capture (ADC) technology, together with bar codes, character recognition, forms recognition, magnetic stripe cards and smart cards.

The technology utilizes a chip that stores information and communicates via radio frequency to one or more antennae. Each antenna in turn communicates to a controller that manages the communication between the antenna and the PC, PLC, or server. To understand the benefits of RFID, an understanding of the components in RFID technology is required. RFID uses a system of tags, antennae, controllers (or readers) and computers.

RF tags come in all sizes and shapes depending on the application requirements. RF tags can even be integrated into labels, composite blocks, even mounted on non-ferrous magnets. There are 2 main groupings of tags: passive and active.

Passive tags do not have an internal source of power and rely on the antenna to supply the power to the tag’s chip to enable reading and writing to the tag. Passive tags typically have smaller storage capacity, slower data transmission rates, and require the antenna to be closer to the tag than an active tag. These tags are generally less expensive and require no maintenance whereas active tags have to be replaced or, have their batteries replaced every few years. Passive tags have a limited number of times a specific address can be written to. This limit is generally in the 100,000+ range.

Active tags contain a battery, which powers the tag’s chip. This allows the tag to initiate communication with the antenna and provides for faster transmission rates and higher storage capacity. Active tags can store excess of 32,000 bytes of information. Some of the active tags allow the battery to be replaced while other tags must be replaced when the battery runs out. The battery life depends on the amount of usage of the tag, but it is generally 7-10 years.