摘要:
In a method for determining the distance between two transmitting and receiving stations, a transmission signal is generated in each station and is transmitted as a series of microwave pulses having a predefined pulse repetition frequency to the other respective station. The coincidence of pulses of the transmission signal sent by the respective station and the signal received by the station is detected in each station as a coincidence event, and the number of pulses transmitted and received by the respective station at the time of the coincidence event is determined. The distance between the stations is then calculated on the basis of the number of the determined pulses.
摘要:
1. Method for determining the distance between two transmitting and receiving stations. 2.1. In automotive engineering transmitting and receiving stations are usually used in keyless locking systems as electronic key modules or evaluation units for identifying the key module. Deactivation of the locking system is prevented, if the key module is not in the immediate vicinity of the evaluation unit. The novel method shall determine the distance between two transmitting and receiving stations with high resolution. 2.3. According to the novel method, a transmission signal is generated in each transmitting and receiving station and is transmitted as a series of microwave pulses having a predefined pulse repetition frequency to the other respective transmitting and receiving station. The coincidence of pulses of the transmission signal sent by the respective transmitting and receiving station and the signal thus received is detected in each transmitting and receiving station as a coincidence event and the number of pulses transmitted and received by the respective transmission and receiving station at the time of the coincidence event is determined. The distance between the transmitting and receiving stations is then calculated on the basis of the number of the determined pulses.
摘要:
In automotive engineering transmitting and receiving stations are usually used in keyless locking systems as electronic key modules or evaluation units for identifying the key module. Deactivation of the locking system is prevented if the key module allocated by means of a clear identification number from the evaluation unit is not in the immediate vicinity of the evaluation unit. The novel method shall determine the distance between two transmitting and receiving stations with high resolution. According to the novel method, a transmission signal (S1, S2) respectively is generated in the transmitting and receiving stations (1, 2) and transmitted as a series of microwave pulses having a predefined pulse repetition frequency (fp1, fp2) to the other respective transmitting and receiving station (2, 1) and received thereby in the form of a received signal. The pulse repetition frequencies (fp1, fp2) of the transmission signals (S1, S2) vary according to a predefined differential frequency value (fd), which is preferably small in relation to the impulse repetition frequencies. Points of coincidence (t11, t12, . . . ; t21, t22) are determined in the transmitting and receiving stations (1, 2), corresponding to those moments in time, when the pulses of the transmission signal (S1, S2) sent by the respective transmitting and receiving station (1, 2) and the received signal E1, E2) received by the respective transmitting and receiving station (1, 2) coincide. The distance between the transmitting and receiving stations is then determined from the distance between the points of coincidence.