DRAFT: This module has unpublished changes.

RFID: (Radio Frequency IDentification) A data collection technology that uses electronic tags for storing data. The tag, also known as an "electronic label," "transponder" or "code plate," is made up of an RFID chip attached to an antenna. Transmitting in the kilohertz, megahertz and gigahertz ranges, tags may be battery-powered or derive their power from the RF waves coming from the reader.


RFID Reader: Usually a microcontroller-based unit with a wound out- put coil, peak detector hardware, comparators, and firmware designed to transmit energy to a tag and read information back from it by detecting the backscatter modulation.


RFID Tag: An RFID device incorporating a silicon memory chip (usually with on-board rectification bridge and other RF front-end devices), a wound or printed input/output coil, and (at lower frequencies) a tuning capacitor.


Carrier: A Radio Frequency (RF) sine wave generated by the reader to transmit energy to the tag and retrieve data from the tag.  This signal has the data encoded within it.


Passive RFID Tags: Passive RFID tags have no power source, but use the electromagnetic waves from the reader to energize the chip and transmit back (backscatter) their data. Passive tags can cost less than a quarter and be read up to approximately 10 feet from the reader's antenna.


Semi-Passive RFID Tags: Semi-passive tags, also called "semi-active" tags, combine passive backscattering with a battery that allows the device to beep, blink, or perform some operation. For example, a semi-passive tag on refrigerated cartons can include a sensor that, when interrogated, reports the temperature range during shipment.


Active RFID Tags: Active RFID tags have a battery that can transmit up to 300 feet indoors and more than a thousand feet outdoors. Used for tracking trailers in yards and containers on the loading dock, active tags cost several dollars and may periodically transmit a signal for readers to pick up or may lie dormant until they sense the reader's signal.


Frequency-shift keying (FSK): Frequency-shift keying (FSK) is a frequency modulation scheme in which digital information is transmitted through discrete frequency changes of a carrier wave.  The simplest FSK is binary FSK (BFSK). BFSK uses a pair of discrete frequencies to transmit binary (0s and 1s) information.


Voltage Regulator: A voltage regulator is an electrical regulator designed to automatically maintain a constant desired voltage level. A voltage regulator may be a feed-forward design or may include negative feedback control loops. It can use an electromechanical mechanism, or alternatively, electronic components.


Phase-shift keying (PSK): Phase-shift keying (PSK) is a digital modulation scheme that conveys data by changing or modulating the phase of a reference signal (the carrier wave).


Amplitude Modulation (AM): Amplitude modulation (AM) is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent.


Pulse Width Modulation: Pulse-width modulation (PWM) is a technique in which the data of a signal is placed within the duty cycle of a pulse wave. PWM, as it applies to a switching transistor (MOSFET), is a way of controlling the gate voltage through delivering energy through a succession of pulses rather than a continuously varying (analog) signal.


Microcontroller: A microcontroller is a small computer on a single integrated circuit containing a processor core, memory, and programmable input/output peripherals. Program memory in the form of NOR flash or OTP ROM is also often included on the chip, as well as a typically small amount of RAM. Microcontrollers are designed for embedded applications, in contrast to the microprocessors used in personal computers or other general-purpose applications.


Modulation: Modulation is the process of encoding source data onto a continuous constant frequency signal or carrier signal.


XBee: XBee is a radio communication module, built by Digi, to the 802.15.4 standard. XBee devices allow us to create a point-to-point or a point-to-many network, depending on usage.


Arduino Shield: Shields are boards that can be plugged on top of the Arduino PCB extending its capabilities.


LCD: LCD stands for Liquid Crystal Display.

DRAFT: This module has unpublished changes.