Autolocation of wireless tire pressure monitoring sensors

• US 7,506,540 B1
• Filed: 02/22/2008
• Issued: 03/24/2009
• Est. Priority Date: 02/22/2008
• Status: Expired due to Fees

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Job, William P.
• Primary Examiner(s): Allen; Andre J
• Application Number:
  US12/036,025
• Time in Patent Office: 396 Days
• Field of Search: 731/46, 731/465, 340/445, 340/447
• US Class Current: 73/146.5
• CPC Class Codes: B60C 23/0416 allocating a corresponding wheel position on vehicle, e.g. front/left or rear/right

Abstract

A tire pressure monitoring system (TPMS) for a vehicle, and related operating methods are provided. The TPMS includes a plurality of tire pressure sensors, each being configured to wirelessly transmit respective sensor signals, and a wireless receiver configured to wirelessly receive and process sensor signals transmitted by the tire pressure sensors. The location of the wireless receiver is biased toward the fore or aft of the vehicle. The wireless receiver has an adjustable sensitivity setting that accommodates wireless signal reception in a key fob mode and a TPMS mode. One operating method for the TPMS involves wirelessly receiving sensor signals transmitted by the tire pressure sensors, determining respective received signal strength (RSS) values for the received sensor signals, and processing the RSS values to resolve whether the received sensor signals were transmitted by a fore tire pressure sensor or an aft tire pressure sensor.

Claims

1. A method of operating a tire pressure monitoring system for a vehicle, the tire pressure monitoring system comprising a plurality of tire pressure sensors, each being configured to wirelessly transmit respective sensor signals, a wireless receiver configured to wirelessly receive and process sensor signals transmitted by the tire pressure sensors, the location of the wireless receiver being biased toward the fore or aft of the vehicle, the method comprising:

wirelessly receiving sensor signals transmitted by the tire pressure sensors, to obtain received sensor signals;

determining respective received signal strength (RSS) values for the received sensor signals, to obtain a plurality of RSS values; and

processing the plurality of RSS values to resolve whether the received sensor signals were transmitted by a fore tire pressure sensor or an aft tire pressure sensor.

2. The method of claim 1, further comprising analyzing content of the received sensor signals to resolve whether the received sensor signals were transmitted by a left tire pressure sensor or a right tire pressure sensor.

3. The method of claim 2, wherein:

each of the sensor signals conveys a sensor identifier that is unique within the tire pressure monitoring system; and

the method further comprises assigning one of a plurality of location labels to each sensor identifier, the location labels consisting of a left front label, a right front label, a left rear label, and a right rear label.

4. The method of claim 1, wherein processing the plurality of RSS values comprises, for each received sensor signal:

comparing its RSS value to a threshold RSS value; and

resolving whether the received sensor signal was transmitted by a fore tire pressure sensor or an aft tire pressure sensor in response to the comparing step.

5. The method of claim 4, wherein:

the location of the wireless receiver is biased toward the fore of the vehicle; and

processing the plurality of RSS values comprises, for each received sensor signal;

comparing its RSS value to at least one threshold RSS value;

indicating that the received sensor signal was transmitted by a fore tire pressure sensor if the RSS value exceeds a high threshold RSS value; and

indicating that the received sensor signal was transmitted by an aft tire pressure sensor if the RSS value does not exceed a low threshold RSS value.

6. The method of claim 4, wherein:

the location of the wireless receiver is biased toward the aft of the vehicle; and

processing the plurality of RSS values comprises, for each received sensor signal;

comparing its RSS value to at least one threshold RSS value;

indicating that the received sensor signal was transmitted by an aft tire pressure sensor if the RSS value exceeds a high threshold RSS value; and

indicating that the received sensor signal was transmitted by a fore tire pressure sensor if the RSS value does not exceed a low threshold RSS value.

7. The method of claim 1, wherein:

the location of the wireless receiver is biased toward the fore of the vehicle; and

processing the plurality of RSS values comprises;

designating two relatively high RSS values and two relatively low RSS values from the plurality of RSS values;

indicating that the received sensor signals having the relatively high RSS values were transmitted by fore tire pressure sensors; and

indicating that the received sensor signals having the relatively low RSS values were transmitted by aft tire pressure sensors.

8. The method of claim 1, wherein:

the location of the wireless receiver is biased toward the aft of the vehicle; and

processing the plurality of RSS values comprises;

designating two relatively high RSS values and two relatively low RSS values from the plurality of RSS values;

indicating that the received sensor signals having the relatively high RSS values were transmitted by aft tire pressure sensors; and

indicating that the received sensor signals having the relatively low RSS values were transmitted by fore tire pressure sensors.

9. The method of claim 1, the wireless receiver being further configured to wirelessly receive and process key fob signals transmitted by a remote key fob for the vehicle, and the method further comprising:

adjusting the wireless receiver to a relatively high sensitivity setting to accommodate reception of key fob signals; and

adjusting the wireless receiver to a relatively low sensitivity setting to accommodate reception of sensor signals transmitted by the tire pressure sensors.

10. The method of claim 9, wherein adjusting the wireless receiver to a relatively low sensitivity is initiated when the vehicle is traveling at greater than a threshold speed.

11. The method of claim 9, wherein adjusting the wireless receiver to a relatively high sensitivity is initiated when the vehicle is traveling at less than a threshold speed.

12. A method of operating a tire pressure monitoring system for a vehicle having a plurality of tire pressure sensors, each being configured to wirelessly transmit respective sensor signals, the method comprising:

wirelessly receiving sensor signals transmitted by the tire pressure sensors, to obtain received sensor signals at an onboard wireless receiver that is biased toward the fore/aft of the vehicle;

determining respective received signal strength (RSS) values for the received sensor signals, to obtain a plurality of RSS values; and

for each of the received sensor signals;

indicating that the received sensor signal was transmitted by a fore/aft tire pressure sensor if the respective RSS value is relatively high; and

indicating that the received sensor signal was transmitted by an aft/fore tire pressure sensor if the respective RSS value is relatively low.

13. The method of claim 12, further comprising analyzing content of the received sensor signals to resolve whether the received sensor signals were transmitted by a left/right tire pressure sensor.

14. The method of claim 12, further comprising analyzing content of the received sensor signals to obtain respective tire pressure measurements.

15. The method of claim 12, the wireless receiver being further configured to wirelessly receive and process key fob signals transmitted by a remote key fob for the vehicle, and the method further comprising optimizing key fob signal reception by the wireless receiver when vehicle speed is less than a low threshold speed.

16. The method of claim 15, further comprising:

adjusting the wireless receiver to a relatively high sensitivity setting to accommodate reception of key fob signals; and

adjusting the wireless receiver to a relatively low sensitivity setting to accommodate reception of sensor signals transmitted by the tire pressure sensors.

17. A tire pressure monitoring system for a vehicle, the system comprising:

a wireless receiver configured to receive tire pressure sensor signals transmitted by a plurality of tire pressure sensors, the location of the wireless receiver being biased toward the fore/aft of the vehicle; and

a processing architecture coupled to the wireless receiver, the processing architecture being configured to;

obtain a received signal strength (RSS) value for each received tire pressure sensor signal; and

for each of the received tire pressure sensor signals, assign a fore/aft tire designation if the respective RSS value is relatively high, or assign an aft/fore designation if the respective RSS value is relatively low.

18. The system of claim 17, the wireless receiver being further configured to wirelessly receive key fob signals transmitted by a remote key fob for the vehicle, and the processing architecture being further configured to process received key fob signals.

19. The system of claim 18, wherein:

the wireless receiver has an adjustable sensitivity setting;

the wireless receiver is configured with a relatively high sensitivity setting to accommodate reception of key fob signals; and

the wireless receiver is configured with a relatively low sensitivity setting to accommodate reception of tire pressure sensor signals.

20. The system of claim 18, the processing architecture being further configured to process each received tire pressure sensor signal by:

comparing its respective RSS value to a threshold RSS value; and

resolving whether the respective tire pressure sensor signal was transmitted by a fore/aft tire pressure sensor in response to the comparing step.