DATA CARRIER WITH AT LEAST TWO DEMODULATORS FOR RECEIVING ASK SIGNALS OF DIFFERING MODULATION INDEX

摘要

A data carrier is adapted to receive a carrier signal (CSM1, CSM2, CSM3), which has been modulated with one of a fixed set of modulation indices (for exemple 100 %, 50 % and 10 %). The data carrier is provided with demodulators (15, 19, 20) sensitive to each of the modulation indices. Means are provided to ensure that only one demodulated signal is passed on to signal processing means (18).