System and method for operating a loop detector
First Claim
Patent Images
1. A method of operating a vehicle detector incorporating a conductive loop and oscillator for detecting vehicles, the method comprising:
- operating a vehicle detector according to a plurality of predetermined characteristics;
determining a relationship between the temperature of the vehicle detector and the plurality of predetermined characteristics of the vehicle detector and storing the relationship in a table in memory;
measuring the temperature of the vehicle detector;
driving the conductive loop using the oscillator;
identifying an adjustment action from the table in memory using the measured temperature;
adjusting at least one of the plurality of predetermined characteristics of the vehicle detector via the adjustment action and subsequently comparing a change in frequency of the oscillator to a detection threshold frequency to determine if a vehicle is in the vicinity of the conductive loop.
1 Assignment
0 Petitions
Accused Products
Abstract
The temperature of an operator circuit is measured. A relationship between the temperature of the operator circuit and characteristics of the operator circuit is determined. The relationship is applied to the measured temperature of the operator circuit to create an adjustment action. The detection threshold is adjusted by the adjustment action.
32 Citations
18 Claims
-
1. A method of operating a vehicle detector incorporating a conductive loop and oscillator for detecting vehicles, the method comprising:
-
operating a vehicle detector according to a plurality of predetermined characteristics; determining a relationship between the temperature of the vehicle detector and the plurality of predetermined characteristics of the vehicle detector and storing the relationship in a table in memory; measuring the temperature of the vehicle detector; driving the conductive loop using the oscillator; identifying an adjustment action from the table in memory using the measured temperature; adjusting at least one of the plurality of predetermined characteristics of the vehicle detector via the adjustment action and subsequently comparing a change in frequency of the oscillator to a detection threshold frequency to determine if a vehicle is in the vicinity of the conductive loop. - View Dependent Claims (2, 3, 4)
-
-
5. In a vehicle detector comprising a conductive loop connected as an electrical component of oscillator circuitry and an oscillation frequency detector, a method comprising:
-
operating the vehicle detector in accordance with predetermined characteristics; measuring a temperature of the vehicle detector; altering the predetermined characteristics of the vehicle detector in response to the measured temperature; and detecting a presence of vehicles in proximity to the conductive loop by detecting changes in a frequency of the oscillation frequency detector in accordance with the altered predetermined characteristics. - View Dependent Claims (6, 7, 8, 9)
-
-
10. A system for adjusting the parameters of a loop detector comprising:
-
a temperature sensor for sensing a temperature; a memory having a mapping relationship stored therein; and a controller coupled to the temperature sensor and the memory, and having an output, the controller programmed to determine an action to adjust characteristics of a vehicle detector based upon the temperature and the mapping relationship, and to apply the adjustment action to alter the characteristics of the vehicle detector at an output. - View Dependent Claims (11, 12, 13, 14, 15)
-
-
16. A method of operating a movable barrier operator comprising:
-
measuring a temperature of an operator circuit; periodically determining a weighted average of a threshold; determining a relationship between the temperature of the operator circuit and a detection threshold; applying the relationship to the measured temperature of the operator circuit to create an adjustment value; and using the weighted average as the threshold and subsequently adjusting the detection threshold by the adjustment value. - View Dependent Claims (17, 18)
-
Specification