Abstract:
Method for preventing security breaches via the two-thief method of attack of passive remote keyless entry systems for vehicles. The method involves the transmission of a signal between a fob and the vehicle, where the level of the signal changes in a particular pattern. At the receiving side, anomalies in the pattern of the received signal (e.g., levels, timing) are detected and used to detect attempts to mimic the signal.
Abstract:
A vehicle control system is described including radio-frequency receiver. The receiver includes an antenna input adapted for connection to an antenna for receiving radio frequency signals, a source of at least a first local oscillator frequency and a second local oscillator frequency, a demodulator for demodulating the signal received via the antenna input with the first local oscillator frequency to generate a first demodulated signal and, separately, for demodulating the signal received via the antenna input with the second local oscillator frequency to generate a second demodulated signal, and a control circuit that evaluates the first and second demodulated signals according to at least one criterion and utilizes for control purposes whichever of the demodulated signals is better, according to that criterion.
Abstract:
Method for preventing security breaches via the two-thief method of attack of passive remote keyless entry systems for vehicles. The method involves the transmission of a signal between a fob and the vehicle, where the level of the signal changes in a particular pattern. At the receiving side, anomalies in the pattern of the received signal (e.g., levels, timing) are detected and used to detect attempts to mimic the signal.
Abstract:
A tire parameter sensing system (12) for a vehicle (10) comprises a vehicle-based unit (42) for receiving parameter signals. A tire-based unit (34) is associated with a tire (16) of the vehicle (10) and rotates with the tire (16). The tire-based unit (34) is located in a communication zone (134) for communicating with the vehicle-based unit (42) through only a portion of each rotation of the tire (16). The tire-based unit (34) is configured to sense a parameter of the tire (16) and to transmit a parameter signal (54) indicative thereof. The system (12) also comprises means (78) for monitoring the rotation of the tire and for providing rotation information indicative of the monitored tire rotation. The tire-based unit (34) is responsive to the rotation information for transmitting the parameter signal (54) while the tire-based unit (34) is located the communication zone (134).
Abstract:
A device (10) is presented for controlling remote convenience function at a vehicle (32) and for interpersonal communication between two operators. The device (10) has components located in a common housing (24). The components include structure (e.g., 14-22) for communicating input from an operator of the device, structure for generating radio frequency signals responsive to the input from the operator of the device, structure for receiving other radio frequency signals from another device responsive to communication input from a operator of another device, and structure for converting the other signals from the operator of the other device into output perceptible by the operator of the device. The output corresponds to the input communicated from the operator of the other device.
Abstract:
A system (10) and associated method for tire condition communication for a vehicle (12). The system (10) includes a sensor (18), associated with a tire (14), to sense at least one tire condition. Transmitter components (22, 24 and 30), associated with the tire (14) and operatively connected to the sensor (18), provide for transmission of a signal (32) that has a data rate and that indicates the sensed tire condition. A receiver unit (40), associated with the vehicle (12), receives the signal (32). The receiver unit (40) includes a plurality of antennas (42A-42N), each for receiving the transmitted signal (32), and a switching device (46) among the plurality of antennas at a rate that is quicker than the data rate of the transmitted signal (32).
Abstract:
A system (10) for remote convenience control of performance of a function includes a portable transmitter unit (14) and a receiver unit (18). In one embodiment, the system (10) is a remote convenience vehicle system. The transmitter unit (14) transmits a signal (16). The signal has a RF frequency at an unknown value within a range of values and conveys a message that contains a function request. Within the receiver unit (18) is superheterodyne circuitry (32) that has a mixer (44). The mixer (44) mixes a RF signal (42) coming from an antenna (28) and a reference frequency signal from a reference oscillator (46), and outputs an intermediate frequency signal (50) conveying the message. A bandpass filter (66) filters the intermediate frequency signal to pass a range of frequency values smaller than a known range of intermediate frequency values. Tuning control circuitry (70) automatically adjusting the bandpass range of the bandpass filter (66) to vary the bandpass range over the intermediate frequency range. Passage detector circuitry (72) senses the intermediate frequency signal passing through the bandpass filter (66) and automatically causes the adjustment of the bandpass range to stop.
Abstract:
Method for preventing security breaches via the two-thief method of attack of passive remote keyless entry systems for vehicles. The method involves the measurement of air travel time of the RF messages between the RKE fob and the vehicle. Multiple round trips between the fob and the vehicle are employed to magnify the distance covered by the messages and thereby allow accurate measurement of the air travel time.
Abstract:
A vehicle control system is described including radio-frequency receiver. The receiver includes an antenna input adapted for connection to an antenna for receiving radio frequency signals, a source of at least a first local oscillator frequency and a second local oscillator frequency, a demodulator for demodulating the signal received via the antenna input with the first local oscillator frequency to generate a first demodulated signal and, separately, for demodulating the signal received via the antenna input with the second local oscillator frequency to generate a second demodulated signal, and a control circuit that evaluates the first and second demodulated signals according to at least one criterion and utilizes for control purposes whichever of the demodulated signals is better, according to that criterion.
Abstract:
An apparatus for monitoring a vehicle condition comprises a sensor for sensing the vehicle condition and a transmitter for transmitting signals indicative of the sensed vehicle condition. The transmitted signals include a first signal set and a second signal set. A receiver mountable on the vehicle is provided for receiving the transmitted signals. The receiver has a first operating state when the vehicle ignition is OFF and a second operating state when the vehicle ignition is ON. The first signal set includes a wake-up portion to wake up the receiver when the receiver is in its first operating state and an information portion. The second signal set includes an information portion. The transmitted signals include at least one first signal set and at least one second signal set during a predetermined time period when the vehicle ignition is OFF and when the vehicle ignition is ON.