Current drain improvements in telematics devices using adjacent cell signal measurement reduction
AssigneeContinental Automotive Systems, Inc.
InventorJames Snider
Life of this patent
Estimating the term…
Abstract
The current drawn by a wireless communications device that is configured to periodically scan control channels can be reduced by reducing the number of control channels to be scanned. The relative strengths of a serving cell control channel and the relative strengths of neighboring cell control channels are determined and the scanning of neighboring cell control channels is discontinued if the communications device is not moving and the signal strength of the serving cell is above a threshold value selected to provide a signal level at which data on a control channel can be reliably recovered.
Claims16
A method of reducing current drain by a vehicular wireless communications device, which is powered by a vehicle battery, the battery capable of being charged by the vehicle, the wireless communications device being configured to periodically scan a serving cell control channel and control channels of a plurality of neighboring cells, and configured to determine the relative strengths of the serving cell control channel and the relative strengths of neighboring cell control channels, the method comprising:
- discontinuing scanning of the neighboring cell control channels, when the vehicle is not charging the vehicle battery and the serving cell control channel signal level is above a threshold.
A method of reducing current drain by a wireless communications device within a vehicle and powered by a vehicle battery capable of being charged by the vehicle, the wireless communications device being configured to periodically scan a serving cell control channel, control channels of a plurality of neighboring cells and configured to determine the relative strengths of the serving cell control channel and the neighboring cell control channels, the method comprising:
- determining a level of a signal on the serving cell control channel signal;
- if the serving cell control channel signal level is above a threshold and if the vehicle is not charging the vehicle battery, discontinuing scanning of the neighboring cell control channels.
An apparatus for reducing current drain by a wireless communications device within a vehicle and which is powered by a vehicle battery, the battery capable of being charged by the vehicle, the wireless communications devices being configured to periodically scan a serving cell control channel and control channels of a plurality of neighboring cells, and configured to determine the relative strengths of the serving cell control channel and the relative strengths of neighboring cell control channels, the apparatus comprising:
- a control channel scanner configured to selectively scan a plurality of control channels and to recover a signal on each control channel to which the control channel scanner is tuned, the control channel scanner scanning only the serving cell control channel responsive to receipt of a control channel signal level indicator and a determination that the vehicle is not charging the vehicle battery and that the service cell control channel signal level is greater than a threshold value;
- and
- a received signal strength determiner (determiner) coupled to the control channel scanner and configured to provide a received signal strength indicator (RSSI) to the control channel scanner, the RSSI having a value corresponding to a strength of a signal received on a control channel, to which the control channel scanner is tuned.
Dependencies are inferred from the claim text.