This paper describes a noncontact IC-card-type automatic passenger gate system. First, the paper briefly presents a review of the technological aspects and then describes the functions and characteristics of the card, transmitter, main unit of the gate, and card checker which constitute the system. In particular, the following issues resolved by the authors are described in detail: (1) The development of insensitive zones in the communication from card to transmitter has been eliminated through the use of subcarriers. (2) Interference during the operation of multiple transmitters has been resolved by reducing the difference among carrier frequencies, using different transmitter. (3) Intercard interference has been eliminated through the use of a polling communications system which can accommodate card holders of multiple cards. (4) The content of the card can be checked through the use of the card checker. Using a highly refined automatic passenger gate system incorporating the functions described above, experiments were performed at an actual station. Processing capacity approximately 20% higher than that available with conventional magnetic card systems was obtained, and the applicability of the new card system to practical situations has been confirmed. In the last section, issues to be resolved in the future popularization of the system are summarized.