1. An RFID reader system for outputting a code of an RFID tag from waves received by a reader antenna, comprising: input circuitry operable to decode from a first one of the waves a first version of the code; and an operational processing block operable to determine whether a fidelity criterion regarding the first version is met, and if so to output the first version of the code, else to derive from the first version a final version of the code that is different from the first version, and to output the final version instead of the first version.