Glossary Of Rfid Terms -- S
Savants
A term used to describe distributed middleware designed by the Auto-ID Center to filter data from EPC readers and pass it on to enterprise systems. It was envisioned that Savants would reside on servers across the EPC Network and pass data to one another and act as a kind of nervous system for the network. The term is being phase out by EPCglobal and many of the functions of Savants are being incorporated in commercial middleware products.
SAW
A technology used for automatic identification in which low power microwave radio frequency signals are converted to ultrasonic acoustic signals by a piezoelectric crystalline material in the transponder. Variations in the reflected signal can be used to provide a unique identity.
Scanner
An electronic device that can send and receive radio waves. When combined with a digital signal processor that turns the waves into bits of information, the scanner is called a reader or interrogator.
Seismic Sensor
A device combining a supersensitive piezoelectric accelerometer with an ultra-low-noise amplifier, used in such applications as earthquake detection, geophysics, geothermal development, structural analysis and mine safety.
Semi-passive tag
Similar to active tags, but the battery is used to run the microchip's circuitry but not to broadcast a signal to the reader. Some semi-passive tags sleep until they are woken up by a signal from the reader, which conserves battery life. Semi-passive tags can cost a dollar or more. These tags are sometimes called battery-assisted tags.
Sensor
A device that responds to a physical stimulus and produces an electronic signal. Sensors are increasingly being combined with RFID tags to detect the presence of a stimulus at an identifiable location.
Shielding
Uses a Faraday cage, Mylar sheet or metal barrier to prevent RF noise from interfering with the ability to read RFID tags, or to prevent RFID readers from interfering with other RF devices.
Signal attenuation
The weakening of RF energy from an RFID tag or reader. The energy emitted by the reader naturally decreases with distance. The rate of decrease is proportional to the inverse square of the distance. Passive UHF RFID tags reflect back a signal at very low power levels. A tag’s reflected signal decreases as the inverse fourth power of the distance between tag and reader. Attenuation can be increased by external factors as well. For instance, water absorbs UHF energy, causing signal attenuation.
Silent Commerce
This term covers all business solutions enabled by tagging, tracking, sensing and other technologies, including RFID, which make everyday objects intelligent and interactive. When combined with continuous and pervasive Internet connectivity, they form a new infrastructure that enables companies to collect data and deliver services without human interaction.
SIM
See subscriber identity module
Singulation
A means by which an RFID reader identifies a tag with a specific serial number from a number of tags in its field. There are different methods of singulation, but the most common is "tree walking", which involves asking all tags with a serial number that starts with either a 1 or 0 to respond. If more than one responds, the reader might ask for all tags with a serial number that starts with 01 to respond, and then 010. It keeps doing this until it finds the tag it is looking for. (See Reader talks first.)
Skimming
Reading an RFID tag on a person without their knowledge or reading a tag surreptitiously.
Slap and ship
A generic term that refers to putting an RFID label on a case or pallet just before it is shipped from a supplier's facility to a retailer's facility. This approach to using RFID is strictly to meet the retailer's requirements and delivers no internal benefits to the supplier.
Slotted antenna
An antenna that consists only of a narrow slot cut into an electrical conductor connected to the transponder. Slotted antennas exhibit the same orientation sensitivity as dipoles.
Smart cards
A credit card or other kind of card with an embedded microchip. When the card uses RFID technology to send and receive data it is called a contactless smart card.
Smart label
A generic term that usually refers to a bar code label that contains an RFID transponder. It's considered "smart" because it can store information, such as a unique serial number, and communicate with a reader.
Smart reader
See intelligent reader
Strap
A type of interposer.
Subscriber identity module
An essential component of a GSM mobile phone. It contains the identity of the subscriber and assures the authentication during the access into the network and provides data storage for other subscriber related information, such as a personal address books.
Substrate
An underlying layer.
Supply Chain Execution System
The optimization of customer response by merging the storage and delivery of finished goods. The execution phase may involve the final assembly and packaging of products within a warehouse environment.
Supply Chain Management System
The process of planning, implementing and controlling the operations of the supply chain to efficiently satisfy customer requirements. Supply-chain management spans all movement and storage of raw materials, work-in-process inventory and finished goods, from the point of origin to the point of consumption.
Surface acoustic wave
A technology used for automatic identification in which low power microwave radio frequency signals are converted to ultrasonic acoustic signals by a piezoelectric crystalline material in the transponder. Variations in the reflected signal can be used to provide a unique identity.
Synchronization
In RFID, the term refers to timing readers or reader antennas near one another so that they don't interfere with one another.