As the antenna passes over the transponder, it energizes the latter with an energy field of 13.56 MHz. The transponder returns its code through frequency modulation to the antenna. A normal reading cycle, including all security checks, is approximately 1 ms.
The system’s operability is guaranteed through fluid, gaseous as well as solid metal-free materials. However, if mounted directly on or within metal, the transponder’s reading distance is influenced.
The Read-Write Transponders are equipped with an EEPROM in which the code is stored. The EE- PROM may be rewritten up to more than 100,000 times. It has 32 bit available for user data.