Power management system and method for vehicle locating unit

• US 10,212,663 B2
• Filed: 01/11/2017
• Issued: 02/19/2019
• 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: Meacci, Fabio, Justice, James A., Rhodes, Jesse L., Goodwin, Michael
• Primary Examiner(s): Gidado, Rasheed
• Application Number:
  US15/403,824
• Publication Number:
  US 20170127353A1
• Time in Patent Office: 769 Days
• 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

Systems and methods for power management systems are disclosed. One embodiment of the invention includes a power management system for a vehicle locating unit, the vehicle locating unit having a receiver for receiving at an assigned message frame an intermittent transmission from a communications source, wherein each intermittent transmission includes at least one assignable message frame, the power management system including a processing device for controlling wake and sleep modes of the receiver and a memory for storing a plurality of memory bit patterns for comparison with a pattern of bits contained in some portion of an assigned message frame, wherein the processing device is configured to perform the following steps: index to the receiver'"'"'s assigned message frame in the intermittent transmission, re-enter wake mode after indexing, and subject the receiver to a constant average current draw.

Claims

1. A system for power management of a vehicle locating unit, the vehicle locating unit having a receiver for receiving at an assigned message frame an intermittent transmission from a communications source, wherein each intermittent transmission includes at least one assignable message frame, the system comprising:

a processing device of the vehicle locating unit in communication with the receiver, the processing device for controlling a wake mode and a sleep mode of the receiver; and

a memory of the vehicle locating unit in communication with the processing device, the memory for storing a plurality of memory bit patterns for comparison with a pattern of bits contained in some portion of an assigned message frame that is assigned to the vehicle locating unit;

wherein the processing device is configured to perform the following;

causing the receiver to enter a wake mode to find a start of an intermittent transmission from the communications source;

in response to finding the start of the intermittent transmission, causing the receiver to enter a sleep mode;

while the receiver is in the sleep mode, indexing to the assigned message frame that is assigned to the vehicle locating unit; and

in response to indexing to the assigned message frame, causing the receiver to re-enter the wake mode and then processing the assigned message frame.

2. The system of claim 1, wherein the processing device is further configured to perform the following:

while the receiver has re-entered the wake mode, comparing the pattern of bits contained in some portion of the assigned message frame with each of the plurality of memory bit patterns; and

in response to detecting a mismatch between the pattern of bits and each of the plurality of memory bit patterns, causing the receiver to re-enter the sleep mode.

3. The system of claim 1, wherein the processing device is further configured to perform the following:

if an expected start of the intermittent transmission is undetected, causing the receiver to re-enter the sleep mode until an expected start of a next intermittent transmission.

4. The system of claim 1, wherein the vehicle locating unit further comprises a transmitter for transmitting a reply code, and wherein at least one intermittent transmission includes at least one of an activate command, a de-activate command, or a speed-up command, the processing device is further configured to perform the following:

upon receipt of an activate command based on a first matching bit pattern, switching the transmitter from a deactivated state to a first slow mode state;

switching the transmitter from the first slow mode state to a second slow mode state after a first predetermined period, the second slow mode state of the transmitter to consume less power than the first slow mode state of the transmitter;

upon receipt of a speed-up command based on a second matching bit pattern, switching the transmitter from at least one of the first slow mode state or the second slow mode state to a fast mode state; and

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

5. The system of claim 4, wherein the processing device is further configured to perform the following:

switching the transmitter from the second slow mode state to a third slow mode state after a third predetermined period, the third slow mode state of the transmitter to consume less power than the second slow mode state of the transmitter; and

switching the transmitter from the third slow mode state to the fast mode state upon receipt of a speed-up command based on a third matching bit pattern.

6. The system of claim 5, wherein the processing device is further configured to de-activate the transmitter from any mode state to a deactivated state upon receipt of a de-activate command based on a fourth matching bit pattern.

7. The system of claim 2, based on detecting the mismatch between the pattern of bits and each of the plurality of memory bit patterns, the processing device is further configured to perform the following:

causing the receiver to remain in the sleep mode until an expected start of a next intermittent transmission;

causing the receiver to enter the wake mode corresponding to the expected start of the next intermittent transmission; and

in response to detecting the expected start of the next intermittent transmission, causing the receiver to re-enter the sleep mode.

8. A method of power management for a vehicle locating unit, the vehicle locating unit having a receiver for receiving at an assigned message frame an intermittent transmission from a communications source, wherein each intermittent transmission includes at least one assignable message frame, a processing device for controlling a wake mode and a sleep mode of the receiver;

and a memory for storing a plurality of memory bit patterns for comparison with a pattern of bits contained in some portion of an assigned message frame that is assigned to the vehicle locating unit, the method comprising;

causing the receiver to enter a wake mode to find a start of an intermittent transmission from the communications source;

in response to finding the start of the intermittent transmission, causing the receiver to enter a sleep mode;

while the receiver is in the sleep mode, indexing to the assigned message frame that is assigned to the vehicle locating unit; and

in response to indexing to the assigned message frame, causing the receiver to re-enter wake mode and then processing the assigned message frame.

9. The method of claim 8, further comprising:

while the receiver has re-entered the wake mode, comparing the pattern of bits contained in some portion of the assigned message frame with each of the plurality of memory bit patterns; and

in response to detecting a mismatch between the pattern of bits and each of the plurality of memory bit patterns, causing the receiver to re-enter the sleep mode.

10. The method of claim 8, further comprising:

if an expected start of the intermittent transmission is undetected, causing the receiver to re-enter the sleep mode until an expected start of a next intermittent transmission.

11. The method of claim 8, further comprising assigning a message frame to the receiver.

12. The method of claim 9, based on detecting the mismatch between the pattern of bits and each of the plurality of memory bit patterns, further comprising:

causing the receiver to remain in sleep mode until an expected start of a next intermittent transmission;

causing the receiver to enter the wake mode corresponding to the expected start of the next intermittent transmission; and

in response to detecting the expected start of the next intermittent transmission, causing the receiver to re-enter the sleep mode.

13. The method of claim 8, wherein the vehicle locating unit further comprises a transmitter for transmitting a reply code, wherein at least one intermittent transmission includes at least one of an activate command, a de-activate command, or a speed-up command, and wherein the method further includes:

based on a first matching bit pattern indicating receipt of an activate command, switching the transmitter from a deactivated state to a first slow mode state;

switching the transmitter from the first slow mode state to a second slow mode state after a first predetermined period, wherein the second slow mode state of the transmitter consumes less power than the first slow mode state of the transmitter.

14. The method of claim 13, further comprising:

based on a second matching bit pattern indicating receipt of a speed-up command, switching the transmitter from at least one of the first slow mode state or the second slow mode state to a fast mode state; and

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

15. The method of claim 14, further comprising:

switching the transmitter from the second slow mode state to a third slow mode state after a third predetermined period, the third slow mode state of the transmitter to consume less power than the second slow mode state of the transmitter; and

based on a third matching bit pattern indicating receipt of a speed-up command, switching the transmitter from the third slow mode state to the fast mode state.

16. The system of claim 15, further comprising:

based on a fourth matching bit pattern indicating receipt of a de-activate command, de-activating the transmitter from any mode state to a deactivated state.