What is one common characteristic of RFID systems?

One common characteristic of RFID systems is that they use radio frequencies for data transmission. RFID, which stands for Radio-Frequency Identification, employs electromagnetic fields to automatically identify and track tags attached to objects. The radio waves facilitate communication between the RFID reader and the tags, allowing for the wireless transfer of information without the need for direct line-of-sight, which distinguishes RFID from other technologies that use physical connections. This capability makes RFID versatile for various applications, including inventory management, asset tracking, and access control.

In contrast, other characteristics mentioned are not universally applicable to all RFID systems. For example, built-in encryption is not a requirement for all RFID systems, and many operate without a physical connection, utilizing their wireless nature. Additionally, while RFID is used in payment systems, its applications extend far beyond that, encompassing numerous industries and use cases.