Determination of wheel sensor position using radio frequency detectors in an automotive remote tire monitor system
View Patent ↗In a remote tire monitor system, radio frequency (RF) signals including tire data are transmitted from a plurality of tire monitors at wheels of a vehicle. At an RF receiver, the signals are received and tire data is detected. The RF signals are detected at a receiving RF detector associated with the transmitting tire monitor. The receiving RF detector produces a transmission indication in response to the received RF signals. A control unit is coupled to the RF receiver and the RF detector. The control unit receives the tire data and the transmission indication and associates a position of the transmitting tire monitor with the tire data in response to transmission indication. This permits automatic update of the position of tire monitors on the vehicle.
1. A method for automatically updating a remote tire monitor system of a vehicle, the method comprising:
storing identification information for each tire monitor of a plurality of tire monitors of the vehicle;
receiving an identifier transmitted by a transmitting tire monitor;
receiving a transmission indication from a receiving radio frequency (RF) detector associated with the transmitting tire monitor, including detecting RF signals at the receiving RF detector;
without demodulating the RF signals, detecting a modulated electrical signal on a wire coupled to the receiving RF detector to produce a wireline indication in response to the RF signals; and
at a control unit, detecting the wireline indication as the transmission indication; and when the identifier does not produce a match with the identification information, updating the identification information using the identifier;
and receiving RF signals at an RF circuit;
demodulating the RF signals to receive tire information; and
locating the identifier in the tire information.
2. The method of claim 1 further comprising:
in response to the wireline indication, reading the identification information from a storage location in memory, the storage location being associated with the receiving RF detector.
3. The method of claim 1 wherein detecting a modulated electrical signal comprises:
detecting a current which has been modulated by an envelope of the RF signals at the receiving RF detector.
4. A method for automatically updating stored identification information for tire monitors of a remote tire monitor system of a vehicle, the system including a plurality of tire monitors associated with tires of the vehicle, a central control unit and a plurality of radio frequency (RF) detectors located proximate respective tire monitors, the method comprising:
at the central control unit, receiving an RF transmission from a tire monitor;
recovering from the RF transmission an identifier transmitted with the RF transmission by the transmitting tire monitor;
at the central control unit, receiving a wireline signal, modulated according to the RF transmission from the transmitting tire monitor, as a transmission indication from a receiving radio frequency (RF) detector associated with the transmitting tire monitor;
retrieving the stored identification information for the transmitting tire monitor as identified by the transmission indication;
comparing the recovered identifier with the retrieved identification information; and
when the identifier does not produce a match with the identification information, updating the identification information using the identifier.
5. The method of claim 4 wherein recovering the identifier from the RF transmission comprises:
receiving RF signals forming the RF transmission at a receiver;
demodulating the RF signals to extract tire data contained in the RF signals; and
associating the tire data with a position of the transmitting tire monitor on the vehicle based on the transmission indication.
6. The method of claim 4 wherein receiving a wireline signal comprises:
at the receiving RF detector, detecting a current which has been modulated by an envelope of the RF transmission.
7. The method of claim 6 further comprising:
without demodulating the RF transmission, modulating a signal in a conductor coupled between the receiving RF detector and the central control unit.