System and method for operating a moveable barrier using a loop detector
View Patent ↗A moveable barrier system includes a loop detector for providing an electrical field. The electrical field has an associated base frequency. The base frequency changes when a vehicle enters the loop detector and the loop detector detects this change. A transmitter device is positioned at the vehicle. The transmitter detects the base frequency of the electrical field as the vehicle becomes positioned in proximity to the loop detector. The transmitter responsively transmits a coded signal to a moveable barrier operator when the base frequency is detected. The coded signal is operable to actuate the moveable barrier operator.
1. A moveable barrier system comprising:
a loop detector that is adapted and configured to generate an electrical field, the electrical field having an associated base frequency, the base frequency being changed by presence of a vehicle and the loop detector configured to detect the change in the base frequency; and
a transmitter device positioned at the vehicle, the transmitter configured to detect the base frequency of the electrical field as the vehicle becomes positioned in proximity to the loop detector and, in response to detecting the base frequency, to wirelessly transmit a coded signal directly to an antenna of a moveable barrier operator, the moveable barrier operator configured to actuate a barrier in response to receiving the coded signal at the antenna directly from the transmitter.
2. The moveable barrier system of claim 1 wherein the electrical field is selected from a group comprising an amplitude modulated signal, a frequency modulated signal, and a spread spectrum modulation signal.
3. The moveable barrier system of claim 1 wherein the coded signal is a query.
4. The moveable barrier system of claim 3 wherein the transmitter device waits to receive a response after the query is transmitted to the moveable barrier operator and responsively transmits a second coded signal to the moveable barrier operator upon detecting the response.
5. The moveable barrier system of claim 1 wherein the transmitter device is mounted on the vehicle.
6. The moveable barrier system of claim 1 wherein the transmitter device is positioned within the vehicle.
7. A system for operating a moveable barrier, the system comprising:
a loop detector that is adapted and configured to generate an electrical field having a base frequency, the base frequency of the loop detector being changed when a vehicle enters the proximity of the loop detector, the loop detector configured to transmit a signal to a moveable barrier entry system to indicate when the frequency has changed and a vehicle is present in proximity to the loop detector and the moveable barrier; and
a transmitter configured to be positioned within a motor vehicle and communicatively coupled to the loop detector and to detect the base frequency of the electrical field of the loop detector and to responsively transmit an actuation message directly to an antenna in communication with a controller in the moveable barrier entry system in response to detecting the base frequency of the electrical field, the controller being configured to actuate the moveable barrier in response to receiving the actuation message.
8. The system of claim 7 wherein the electrical field is modulated.
9. The system of claim 8 wherein the electrical field is modulated by a technique selected from a group of techniques comprising amplitude modulation (AM), frequency modulation (FM) and spread spectrum (SS) modulation.
10. The system of claim 7 wherein the electrical field comprises a coded signal.
11. The system of claim 7 wherein the actuation message comprises a query.
12. A method of operating a transmitter positioned in a vehicle, the method comprising:
producing an electric field having a base frequency at a loop detector;
changing the base frequency of the electric field by moving a vehicle in proximity of the loop detector;
detecting the base frequency of the electrical field at a transmitter;
in response to detecting the base frequency of the electrical field, directly and wirelessly sending a signal from the transmitter to an antenna of a movable barrier operator; and
performing an action at the operator to actuate the movable barrier operator in response to the movable barrier operator's antenna receiving the signal directly from the transmitter.
13. The method of claim 12 wherein detecting the change comprises detecting a change in a base frequency of the loop detector.
14. The method of claim 12 wherein the detecting comprises detecting a modulated signal.
15. The method of claim 14 wherein the detecting comprises detecting a modulated signal selected from a group comprising an amplitude modulated (AM) signal, a frequency modulated (FM) signal and a spread spectrum (SS) modulated signal.
16. The method of claim 14 wherein the detecting comprises detecting a signal encrypted according to a predetermined fixed or variable code.
17. The method of claim 14 wherein the sending the signal comprises sending a query to the barrier operator.
18. The method of claim 17 further comprising, in response to the query, receiving a response message from the barrier operator at the transmitter.