Abstract: Apparatus for use in a vehicle equipped with a vehicle-to-vehicle communication system. A remote keyless entry fob is provided for remote control of vehicle access.

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 method for defeating a two-thief attack on a passive RKE system by using frequency hopping. Radio frequency signals are transmitted between a fob and a vehicle. The transmitted signals hop between at least two radio frequency transmitting channels in a particular pseudo-random pattern known to the vehicle. At the vehicle, the transmitted signals are received in a process that is sequentially adjusted to take account of the known characteristics of each portion of the known pattern. Anomalies in the pattern of the received signals are detected and, if the anomalies exceed permissible limits, access to said vehicle is blocked.

Abstract: Apparatus for use in a vehicle equipped with a vehicle-to-vehicle communication system. A remote keyless entry fob is provided for remote control of vehicle access. The fob includes a receiver for receiving a message broadcast by the vehicle-to-vehicle communication system and a memory for storing at least some elements of the message.

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: Apparatus for use in a vehicle equipped with a vehicle-to-vehicle communication system. A remote keyless entry fob is provided for remote control of vehicle access. The fob includes a receiver for receiving a message broadcast by the vehicle-to-vehicle communication system and a memory for storing at least some elements of the message.

Abstract: A method and apparatus for controlling a vehicle based transmitter/receiver system including transmitting a first signal portion at a first baud rate and second signal portion at a second baud rate where the first baud rate is faster than the second baud rate, the first signal portion including a wake-up portion, and controlling the receiver to periodically wake up to receive the first signal portion and stay awake to receive the second signal portion only if the wake-up portion of the received signal is valid.

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: 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.

Abstract: A method for identifying tire location including the steps of transmitting a low frequency signal at different power levels and receiving radio frequency identification signals. Tire identification and location based on low frequency power level for two tire transmitters is determined. Radio frequency signals from two different tire transmitters are received and tire identification and location are determined based on radio frequency signal strength.

Abstract: A method is provided for determining tire location in a tire pressure monitoring system having the steps of generating an initiation frequency signal having a controllable output adapted to be received by a selected one of a plurality of tires of the tire pressure monitoring system. At least two tires of the tire pressure monitoring system have associated initiation signal receivers. The method also includes transmitting a response signal from the selected tire receiving the initiation signal, the response signal having at least a unique identification signal portion associated with the selected tire. The method also receives the transmitted response signal and associates the identification signal with a location of the selected tire.

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.

Abstract: A method for identifying tire location including the steps of transmitting a low frequency signal at different power levels and receiving radio frequency identification signals. Tire identification and location based on low frequency power level for two tire transmitters is determined. Radio frequency signals from two different tire transmitters are received and tire identification and location are determined based on radio frequency signal strength.

Abstract: A method for receiving data from and associating locations of a plurality of tire condition sensors in a vehicle comprises the step of mounting a first directional antenna in the vehicle oriented in a first direction to receive signals from an associated transmitter of at least some of said tire condition sensors. A second directional antenna is mounted in the vehicle oriented in a second direction to receive signals from an associated transmitter of others of said tire condition sensors. Signal strength of any received signals is determined, and sensor locations are determined by determining a differential signal value.

Abstract: A method is provided for determining tire location in a tire pressure monitoring system having the steps of generating an initiation frequency signal having a controllable output adapted to be received by a selected one of a plurality of tires of the tire pressure monitoring system. At least two tires of the tire pressure monitoring system have associated initiation signal receivers. The method also includes transmitting a response signal from the selected tire receiving the initiation signal, the response signal having at least a unique identification signal portion associated with the selected tire. The method also receives the transmitted response signal and associates the identification signal with a location of the selected tire.

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: The invention provides a vehicle wheel arch (18) of the type including an antenna (20) for interacting with a device (22) carried by an assembly (12) of a wheel (14) and a tire (16). The wheel arch includes a shield (24) overlying the antenna (20) beside the radially-inner face of the wheel arch (18), said shield (24) being suitable for retaining matter (26) at a certain distance from the antenna (20).

Abstract: A tire parameter sensing system (12) for a vehicle (10) having a plurality of tires (16, 18, 20, 22) comprises a plurality of tire-based units (34, 36, 38, 40). Each tire-based unit (34, 36, 38, 40) being configured to receive initiation signals and, in response thereto, to transmit response signals (54, 56, 58, 60). A vehicle-based unit (42) receives the response signals (54, 56, 58, 60) and transmits the initiation signals (90). A plurality of signal masking devices (44, 46, 48, 50) is coupled to the vehicle-based unit (42). The signal masking devices (44, 46, 48, 50) have associated tire locations on the vehicle (10) and are actuatable for masking the initiation signals (90) near the associated tire locations. The vehicle-based unit (42) controls the signal masking devices (44, 46, 48, 50) so as to control the tire location from which a tire-based unit responds to the initiation signals (90).