Power management system and method for vehicle locating unit

• US 20110095915A1
• Filed: 10/23/2009
• Published: 04/28/2011
• Est. Priority Date: 10/23/2009
• Status: Active Grant

• Current Assignee: Calamp Wireless Networks Inc. (CalAmp Corporation)
• Original Assignee: LoJack Corporation (Solera Holdings Incorporated)
• Inventors: Rhodes, Jesse, Goodwin, Michael, Justice, James
• Granted Patent: US 8,618,957 B2
• Time in Patent Office: Days
• US Class Current: 340/988
• CPC Class Codes: B60R 25/102 a signal being sent to a remote location, e.g. a radio signal being transmitted to a police station, a security company or the owner
• CPC Class Codes: B60R 25/403 Power supply in the vehicle
• CPC Class Codes: G08G 1/20 Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0235 where the received signal is a power saving command
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Improved power management for a vehicle locating unit is achieved by receiving a transmission from a communication source, each transmission including at least one message frame having a data field and at least one auxiliary field; entering a wake mode upon indexing the assigned message frame of the receiver in the transmission; matching the pattern of bits of at least one auxiliary field of the indexed frame with one or more stored patterns of bits expected for that auxiliary field; and returning to the sleep mode as soon as a mismatch is determined or processing the message if no mismatch occurs.

Claims

1. A vehicle locating unit with improved power management, the vehicle locating unit comprising;

a receiver for receiving a transmission from a communications source;

each transmission including at least one message frame having a data field and at least one auxiliary field;

a power management system responsive to said receiver and configured to enter a sleep mode after detecting a transmission and enter a wake mode upon indexing the assigned message frame of the receiver in the transmission, matching the pattern of bits of at least one auxiliary field of the indexed frame with one or more stored patterns of bits expected for that auxiliary field, and either returning to the sleep mode as soon as a mismatch is determined or processing the message if no mismatch occurs.

2. The vehicle locating unit of claim 1 in which there are a plurality of message frames in each transmission.

3. The vehicle locating unit of claim 1 in which there are one or more auxiliary fields in each message frame.

4. The vehicle locating unit of claim 1 in which said power management system includes a processor for controlling said wake and sleep modes.

5. The vehicle locating unit of claim 1 in which said power management system includes a memory for storing said one or more patterns of bits expected for an auxiliary field.

6. An improved method of power management for a vehicle locating unit comprising:

receiving a transmission from a communication source, each transmission including at least one message frame having a data field and at least one auxiliary field;

entering a wake mode upon indexing the assigned message frame of the receiver in the transmission;

matching the pattern of bits of at least one auxiliary field of the indexed frame with one or more stored patterns of bits expected for that auxiliary field; and

returning to the sleep mode as soon as a mismatch is determined or processing the message if no mismatch occurs.

7. The improved method of power management of claim 6 in which there are a plurality of message frames in each transmission.

8. The improved method of power management of claim 6 in which there are one or more auxiliary fields in each message frame.

9. A vehicle locating unit with improved power management, the vehicle locating unit comprising:

a transmitter for transmitting reply codes;

a receiver for receiving activate commands, de-activate commands and speed-up commands;

a power management system responsive to said receiver and configured to switch said transmitter from a de-activated state to a slow mode state upon receipt of an activate command, to switch said transmitter from said slow mode state to a second, slower, slow mode state after a predetermined period; and

upon receipt of a speed-up command to switch said transmitter from either of the slow mode state or second slow mode state to a fast mode state and to switch said transmitter from the fast mode state to said slow mode state after a predetermined period.

10. The vehicle locating unit of claim 9 in which said power management system is further configured to switch said transmitter from said second slow mode state to a third, slower, slow mode state after a preselected period, and to switch said transmitter from said third slow mode state to said fast mode state upon receipt of a speed-up command.

11. The vehicle locating unit of claim 10 in which said power management system is further configured to de-activate said transmitter from any of said mode states to a de-activated state upon receipt of a de-activate command.

12. An improved method of power management for a vehicle locating unit having a transmitter for transmitting reply codes and a receiver for receiving activate commands, de-activate commands and speed-up commands comprising:

switching the transmitter from a de-activate state to a slow mode state upon receipt of an activate command;

switching the transmitter from the slow mode state to a second, slower mode state after a predetermined period;

switching, upon receipt of a speed-up command, the transmitter from either of the slow mode state or second slow mode state to a fast mode state; and

switching the transmitter from the fast mode state to the slow mode state after a predetermined period.

13. The improved method of power management of claim 12 further including switching the transmitter from the second slow mode state to a third, slower, slow mode state after a preselected period, and switching the transmitter from the third slow mode state to the fast mode state upon receipt of the speed-up command.

14. The improved method of power management of claim 13 further including de-activating the transmitter from any of the mode states to a de-activated state upon receipt of a de-activate command.