An ultrahigh frequency radio frequency identification, or UHF RFID reader, is a device that might resemble a small electronics component or keypad with display, designed to identify and authenticate items or products containing a corresponding UHF tag. Devices based on this technology are used in numerous industries and applications, such as inventory control and asset management, as well as warehouse logistics, security, and personnel management. Transmission of signals occurs wirelessly with radio waves, permitting identification without physical contact through obstructions like clothing and container materials. Common UHF bands for the technology range from 860 to 960 megahertz (MHz), around the mobile phone and industrial, scientific, and medical (ISM) band, up to 2.4 gigahertz (GHz). Devices can be handheld units, small desktop pads, or fixed, mounted equipment; they can also be designed as tabletop and rack-mounted components, or fixtures elevated on poles.
Three essential components comprise the UHF RFID reader system. These consist of the reader/antenna unit; the transponder-containing tag, which possesses a data-encoded integrated circuit; and the software/computer system, designed to process and manage information. The design employed by a UHF RFID reader essentially depends upon its intended placement and use. For example, those used in manufacturing are employed to track parts, reduce defects, and optimize production throughput, and are deployed in numerous designs according to their field uses. Similarly, this technology is often engaged in supply chain management in order to track shipments and automate stages of the supply chain.
Other applications may include placement of UHF RFID reader devices in order to collect road tolls as well as permit entry into office buildings. One advantage of this technology is to permit wireless contact and reduce wear and tear of physical devices such as swipe cards and keys. They've also been used to track patients and pets, prevent loss in retail settings, and establish authenticity of items to reduce trade in pirated goods.
Handheld UHF RFID reader units serve inspectors and inventory takers by providing mobile capabilities, allowing spot checks and site inspections. Small components can be fixed in locations for site-specific uses or to take regular readings, at places including customs desks in airports, point-of-sale cashiers in retail outlets, and automated service or industrial processes. Others might be combined with technologies such as barcode scanners and integrated in other equipment. Some are used in handheld guns for aiming at moving products and difficult-to-reach items.
Although varied in design, these tools are generally influenced by the same factors that affect UHF radio transmissions, such as accuracy and efficiency of output signals, interferences, sensitivities, and ranges. Power levels, amplification, and bandwidth characteristics are also contributing factors. UHF RFID reader devices employ digital data streams that carry signal transmissions over varying distances. Received signals are converted into digital data, which can then be decoded and interpreted. Systems may differ, however, in the types of tags read; passive tags use the energy deployed by the reader, while active tags contain an onboard battery to increase response range.