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 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:
A circuit (14) for use in a tire (16) of a vehicle (10) having a tire parameter sensing system (12) includes a battery (60) for supplying electrical energy. The battery (60) has an equivalent series resistance (64) that varies inversely with temperature. The circuit (14) further includes a current control device (90) that is responsive to at least one of an output voltage of the battery and temperature for adjusting a current draw from the battery (60) to insure a predetermined minimum output voltage from the battery (60).
Abstract:
An antenna (96) for use in inductive coupling two devices (34 and 42) includes a first coil (180) having a first inductance value, a second coil (190) having a second inductance value, and a capacitor (198) having a capacitance value. The first and second coils (180 and 190) and the capacitor (198) form a tank circuit (196) having a predetermined resonant frequency. The capacitance value of the capacitor (198) varies inversely to an equivalent inductance value of the tank circuit (196) for providing the predetermined resonant frequency. The first and second coils (180 and 190) are connected in parallel with one another so that the equivalent inductance value of the tank circuit (196) is less than each of the first and second inductance values and the capacitance value of the capacitor (198) is maintained above a predetermined threshold value for providing stability to the tank circuit (196).
Abstract:
A tire parameter sensing system (12) for sensing a parameter of a tire (16) includes a power transmitting antenna (44) that is actuatable for producing a magnetic field at a location of the tire (16). A rim (140) upon which the tire (16) is mounted includes first and second magnetically conductive surface portions (160 and 168) that form a drop well (156). A tire-based unit (34) is mounted in the drop well (156) so that a coil antenna (96) of the tire-based unit (34) is located adjacent to both the first and second magnetically conductive surface portions (160 and 168). The central axis of the coil antenna (96) extends in a direction parallel to the first magnetically conductive surface portion (160) and the first and second magnetically conductive surface portions (160 and 168) guide magnetic flux of the magnetic field to the coil antenna (96).
Abstract:
An apparatus (10) comprises a controller (82) for receiving a control parameter. At least one tire condition sensor (26-32) senses a tire condition and transmits a tire condition signal (34) indicative of the sensed tire condition. A receiver (78) receives the tire condition signal (34) and compares the received tire condition signal (34) to a changeable threshold to output a digital signal indicative of the received tire condition signal (34). The changeable threshold changes at time intervals determined by a time constant of the receiver (78). The time constant of the receiver (78) is variable. The controller (82) is operatively connected to the receiver (78) and varies the time constant of the receiver (78) in response to the received control parameter.
Abstract:
A system (10) for a vehicle (12), wherein the system includes transmitter components (26, 28), located at the vehicle, that are operable to send communication that conveys a vehicle system status. A portable receiver unit (14) is operable to receive the communication that conveys the vehicle system status. An operator (76) of the vehicle (12) carries the portable receiver unit (14) upon leaving the vehicle. A controller (22) senses a condition indicative of the vehicle operator (76) leaving the vehicle (12) and enables the communication from the transmitter components (26, 28) to the portable receiver unit (14) in response to the sensed condition indicative of the vehicle operator (76) leaving the vehicle (12). Preferably, a device (44) enables operation of the portable receiver unit (14) in response to the sensed condition indicative of the vehicle operator (76) leaving the vehicle (12).
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:
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).