Wireless communications between a vehicle base station and transponder is authenticated. Two or more antennas including at least one within a vehicle are respectively driven using driving currents multiplied by different superposition factors for at least two iterative cycles. Separate vector components of the respective fields emitted by the antennas are used for calculating superposition factors. For each cycle, each antenna is concurrently driven using the same phase respectively using the driving currents multiplied by the superposition factors, and superposed vector components are detected for a superposed signal including signals from both antennas. Communications are authenticated via the detected superposed vector components for each for the superposed signal of each cycle being within a system error-based range of the sum of the vector components for each of the antennas as multiplied respectively by the superposition factors for the antenna from which the vector components are received.