Keyless entry multi-channel RKE system
View Patent ↗A remote keyless entry system includes a portable communication device for communicating with an electronic control module of a transportation vehicle. The transmitter has at least two selectable communication channels for broadcasting communications signals to the transportation vehicle. A vehicle based electronic control module communicates with the portable communication device. The electronic control module includes a receiver that includes at least two selectable communication channels for receiving RF signals from the portable communication device. A controller selectively energizes the receiver for measuring a RSSI voltage level of each selectable communication channel of the receiver over respective predetermined time periods. The controller determines which of the at least two selectable communication channels includes a lowest noise level based on the measured RSSI voltage level. A channel status update signal is broadcast from the electronic control module to the portable communication device identifying the selected communication channel having the lowest noise level.
1. A remote keyless entry system for a vehicle comprising:
(1) a keyless entry module adapted to be disposed within a vehicle and including a receiving circuit, a keyless entry module controller, and a transmitter, wherein:
(a) the receiving circuit is adapted to receive a remote keyless entry command on a selected one of a plurality of communication channels;
(b) the keyless entry module controller is responsive to the receipt of a remote keyless entry command by the receiving circuit for generating a signal that is adapted to cause a remote keyless entry function to be performed on the vehicle;
(c) the keyless entry module controller periodically turns on the receiving circuit during all operational and non-operational times of the vehicle, measures a noise level on each of the plurality of communication channels, and generates an identifier that identifies a selected one of the plurality of communication channels that has a lowest noise level; and
(d) the transmitter transmits a signal that is representative of the identifier; and
(2) a portable communication device including a transceiver and a portable communication device controller, wherein:
(a) the transceiver is adapted to receive the signal that is representative of the identifier;
(b) the portable communication device controller is responsive to the receipt of the signal that is representative of the identifier for generating a signal that is representative of the selected one of the plurality of communication channels having the lowest noise level; and
(c) the transceiver is responsive to the signal from the portable communication device controller for transmitting a remote keyless entry command on the selected one of the plurality of communication channels having the lowest noise level in response to a manual activation,
wherein the keyless entry module controller measures a received signal strength indicator (RSSI) voltage level on each of the plurality of communication channels and identifies which one of the plurality of communication channels has an RSSI voltage level that is closest to a predetermined voltage level defined by a channel in which no signal is present and no noise is present.
2. The remote keyless entry system defined in claim 1 wherein the keyless entry module controller measures the RSSI voltage level at periodic time intervals.
3. The remote keyless entry system defined in claim 1 wherein the keyless entry module controller measures the RSSI voltage level upon a predetermined event occurring.
4. The remote keyless entry system defined in claim 3 wherein the predetermined event is a closing of a vehicle door.
5. The remote keyless entry system defined in claim 3 wherein the predetermined event is an opening of a vehicle door.
6. The remote keyless entry system defined in claim 3 wherein the predetermined event is a turning of an ignition key to an ignition off position.
7. The remote keyless entry system defined in claim 3 wherein the predetermined event is a locking of a vehicle door.