Method and system for calculating a user account balance in a recognition system

摘要

A system and method in which a transponder (14) is operable to transmit an original user account balance to an interrogator (12), which in turn calculates a revised user account balance and transmits the revised user account balance to the transponder (14). In one embodiment of the invention, the transponder (14) is further operable to transmit a verification user account balance back to the interrogator (12), which then compares verification user account balance to the revised user account balance that was earlier calculated and stored in an interrogator memory.