Interrogator (Reader)

An RFID Interrogator, also called a Reader, is an electronic device that receives the radio signal from the tag. In many cases, the interrogator also generates the interrogation signal. Interrogators require a power supply, network connection, and antenna in order to function. Depending on application, these components may be separate or integrated. Interrogators come in various form factors and methods of operation. Form factors are generally grouped together as fixed, hand held, and mobile, although the distinctions are blurry. The methods of operation group into passive / semi-passive and active systems.

Form Factors

There is overlap in the general categories presented below, especially between hand held and mobile devices.

Fixed

Fixed interrogators are designed to be mounted near conveyor belts, doors or other choke points. They normally require an external power source. Communication with the host network may be either wired or wireless.

Hand Held

Hand held interrogators are typically gun-style devices. They can be either untethered, employing a battery and wireless network connectivity, or tethered, with power and possibly network connectivity supplied through a cord.

By convention, other hand held form factors such as mobile phones and PDAs are classified as mobile devices.

Mobile

See Also

Backscatter; Inductive Coupling; Reader Chip Sets