Which of the following statements are correct regarding Radio Frequency Identification (RFID) technology?

A. RFID refers to a wireless system comprising two components: tags and readers.

B. The reader is a device that has one or more antennas that emit radio waves and receive signals back from the RFID tag.

C. Passive KFID tags are powered by the reader and do not have a battery.

Choose the correct answer from the options given below:

The correct answer is A, B and C.

Let us analyze each statement step-by-step to understand why they are all correct regarding Radio Frequency Identification (RFID) technology:

Statement A: RFID refers to a wireless system comprising two components: tags and readers.
This statement is correct. An RFID system is a wireless communication technology that uses electromagnetic fields to identify and track tags attached to objects. The system fundamentally consists of two primary components: the RFID tag (which holds the data) and the RFID reader (which interrogates the tag and retrieves the data).

Statement B: The reader is a device that has one or more antennas that emit radio waves and receive signals back from the RFID tag.
This statement is correct. The RFID reader (also known as the interrogator) contains a transmitter and receiver module along with one or more antennas. The antenna broadcasts radio waves to activate/communicate with the tag and then captures the backscattered or transmitted radio frequency signals sent back by the tag.

Statement C: Passive RFID tags are powered by the reader and do not have a battery.
This statement is correct. Unlike active RFID tags, which have an onboard battery power source, passive RFID tags do not possess an internal battery. Instead, they operate using electromagnetic induction or electromagnetic wave coupling: the radio frequency energy emitted by the reader's antenna induces a tiny electrical current in the tag's antenna, which is sufficient to power the integrated circuit (microchip) inside the tag and transmit its stored information back to the reader.

Since all three statements A, B, and C are correct, the option containing all three is the correct choice.