Implantable medical device and method for managing advertising and scanning schedules
Methods and devices for managing establishment of a communications link between an external instrument (EI) and an implantable medical device (IMD) are provided. A method performed by the EI includes scanning one or more channels for an advertisement notice transmitted by the IMD in accordance with a scanning schedule, wherein the scanning schedule defines a temporal pattern of scanning windows that are separated by one or more scanning intervals. The method also includes changing the scanning schedule, in response to a duration of the scanning the one or more channels exceeding a predetermined threshold without a valid advertisement notice being received by the EI from the IMD, and scanning the one or more channels for the advertisement notice in accordance with the scanning schedule as changed, wherein the scanning schedule as changed defines a different temporal pattern of scanning windows that are separated by one or more scanning intervals.
1. A method performed by an external instrument (EI) to enable the EI to establish a communication session with an implantable medical device (IMD) using a wireless communication protocol, the method comprising:
scanning one or more channels for an advertisement notice transmitted by the IMD in accordance with a scanning schedule, wherein the scanning schedule defines a temporal pattern of scanning windows that are separated by one or more scanning intervals;
determining whether a valid advertisement notice was received by the EI from the IMD within one of the scanning windows;
determining a duration of the scanning the one or more channels exceeds a predetermined threshold without a valid advertisement notice being received by the EI from the IMD; and
changing the scanning schedule, in response to the duration of the scanning the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the EI from the IMD, and scanning the one or more channels for the advertisement notice in accordance with the scanning schedule as changed, wherein the scanning schedule as changed defines a different temporal pattern of scanning windows that are separated by one or more scanning intervals.
2. The method of claim 1 , wherein:
the scanning schedule includes a first scanning interval between first and second scanning windows and a second scanning interval between the second scanning window and a third scanning window;
the first and the second scanning intervals differ from one another; and
the changing the scanning schedule, in response to the duration of the scanning one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the EI from the IMD, comprises changing one of the first and the second scanning intervals.
3. The method of claim 1 , wherein:
the scanning schedule includes a first scanning interval between first and second scanning windows and a second scanning interval between the second scanning window and a third scanning window;
the first and the second scanning intervals differ from one another; and
the changing the scanning schedule, in response to the duration of the scanning one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the EI from the IMD, comprises changing both of the first and the second scanning intervals.
4. The method of claim 1 , wherein:
the scanning schedule includes a first scanning interval between first and second scanning windows and a second scanning interval between the second scanning window and a third scanning window;
the first and the second scanning intervals differ from one another; and
the changing the scanning schedule, in response to the duration of the scanning the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the EI from the IMD, comprises adding a third scanning interval that differs from both of the first and the second scanning intervals.
5. The method of claim 1 , wherein:
the changing the scanning schedule in response to the duration of the scanning the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the EI from the IMD, comprises switching between predetermined scanning schedules.
6. The method of claim 1 , further comprising:
transmitting a connection request from the EI to the IMD in response to determining that a valid advertisement notice was received by the EI from the IMD;
determining whether a connection response was received by the EI from the IMD; and
establishing a communication link between the EI and the IMD, in response to determining that the connection response was received by the EI from the IMD.
7. The method of claim 1 , wherein the scanning the one or more channels for an advertisement notice transmitted by the IMD in accordance with the scanning schedule comprises:
setting a scanning interval timer to at least two different scanning intervals based on the scanning schedule; and
setting a window duration timer that defines a duration of each of the scanning windows.
8. The method of claim 7 , wherein the setting the scanning interval timer comprises:
setting the scanning interval timer to a first scanning interval based on the scanning schedule; and
setting the scanning interval timer to a second scanning interval based on the scanning schedule, in response to determining that the scanning interval timer, which had been set to the first scanning interval, timed out without a valid advertisement notice being received by the EI from the IMD.
9. The method of claim 7 , wherein prior to the scanning the one or more channels in accordance with the scanning schedule, the method further comprises obtaining the scanning schedule from a memory.
10. The method of claim 1 , wherein:
the scanning windows are grouped in a first segment as defined by the scanning schedule; and
the scanning schedule also defines a quiescent segment that is devoid of any scanning windows.
11. An external instrument (EI) that is configured to establish a communication session with an implantable medical device (IMD) using a wireless communication protocol, the EI comprising:
a memory that stores a scanning schedule that defines a temporal pattern of scanning windows that are separated by one or more scanning intervals;
a processor configured to access the scanning schedule stored in the memory; and
a receiver configured to selectively scan, under control of the processor, one or more channels for an advertisement notice transmitted by the IMD; and
the processor also configured to
cause the receiver to scan the one or more channels for the advertisement notice transmitted by the IMD in accordance with the scanning schedule;
determine whether a valid advertisement notice was received by the EI from the IMD within one of the scanning windows;
determine whether a duration of the receiver scanning the one or more channels exceeds a predetermined threshold without a valid advertisement notice being received by the receiver of the EI from the IMD; and
change the scanning schedule, in response to the duration of the receiver scanning the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the receiver of the EI from the IMD, and cause the receiver to scan the one or more channels for the advertisement notice in accordance with the scanning schedule as changed, wherein the scanning schedule as changed defines a different temporal pattern of scanning windows that are separated by one or more scanning intervals.
12. The EI of claim 11 , wherein:
the scanning schedule includes a first scanning interval between first and second scanning windows and a second scanning interval between the second scanning window and a third scanning window;
the first and the second scanning intervals differ from one another; and
the processor is configured to change the scanning schedule, in response to the duration of the receiver scanning the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the receiver of the EI from the IMD, by changing one of the first and the second scanning intervals.
13. The EI of claim 11 , wherein:
the scanning schedule includes a first scanning interval between first and second scanning windows and a second scanning interval between the second scanning window and a third scanning window;
the first and the second scanning intervals differ from one another; and
the processor is configured to change the scanning schedule, in response to the duration of the receiver scanning the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the receiver of the EI from the IMD, by changing both of the first and the second scanning intervals.
14. The EI of claim 11 , wherein:
the scanning schedule includes a first scanning interval between first and second scanning windows and a second scanning interval between the second scanning window and a third scanning window;
the first and the second scanning intervals differ from one another; and
the processor is configured to change the scanning schedule, in response to the duration of the receiver scanning the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the receiver of the EI from the IMD, by adding a third scanning interval that differs from both of the first and the second scanning intervals.
15. The EI of claim 11 , wherein:
the processor is configured to change the scanning schedule in response to the duration of the receiver scanning the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the receiver of the EI from the IMD, by switching between predetermined scanning schedules stored in the memory.
16. The EI of claim 11 , further comprising:
a transmitter;
wherein the processor is further configured to
cause the transmitter to transmit a connection request to the IMD in response to a valid advertisement notice being received by the receiver of the EI from the IMD;
determine whether a connection response was received by the receiver of the EI from the IMD; and
establish a communication link between the EI and the IMD, in response to determining that the connection response was received by the receiver of the EI from the IMD.
17. The EI of claim 11 , wherein to cause the receiver to scan the one or more channels for the advertisement notice transmitted by the IMD in accordance with the scanning schedule, the processor is configured to:
set a scanning interval timer to at least two different scanning intervals based on the scanning schedule; and
set a window duration timer that defines a duration of each of the scanning windows.
18. The EI of claim 17 , wherein to set the scanning interval timer to at least two different scanning intervals based on the scanning schedule, the processor is configured to:
set the scanning interval timer to a first scanning interval based on the scanning schedule; and
set the scanning interval timer to a second scanning interval based on the scanning schedule, in response to the scanning interval timer, which had been set to the first scanning interval, timing out without a valid advertisement notice being received by the receiver of the EI from the IMD.
19. The EI of claim 11 , wherein:
the scanning windows are grouped in a first segment as defined by the scanning schedule; and
the scanning schedule also defines a quiescent segment that is devoid of any scanning windows.
20. The EI of claim 11 , wherein the EI is selected from the group consisting of: an IMD programmer; a workstation; a portable computer; a tablet computer; a smart phone; a smart watch; or a laptop computer.
21. The EI of claim 20 , wherein the IMD, with which the EI is configured to establish the communication session, is selected from the group consisting of: an implantable neurostimulator; an implantable pacemaker; an implantable cardioverter-defibrillator (ICD); an implantable cardiac rhythm management (CRM) device; and an implantable pulse generator (IPG).
22. A non-transitory computer readable storage medium for enabling an external instrument (EI) to establish a communication session with an implantable medical device (IMD) using a wireless communication protocol, the computer readable storage medium comprising instructions to:
scan one or more channels for an advertisement notice transmitted by the IMD in accordance with a scanning schedule, wherein the scanning schedule defines a temporal pattern of scanning windows that are separated by one or more scanning intervals;
determine whether a valid advertisement notice was received by the EI from the IMD within one of the scanning windows;
determine a duration of the scan of the one or more channels exceeds a predetermined threshold without a valid advertisement notice being received by the EI from the IMD; and
change the scanning schedule, in response to the duration of the scan of the one or more channels exceeding the predetermined threshold without a valid advertisement notice being received by the EI from the IMD, and scan the one or more channels for the advertisement notice in accordance with the scanning schedule as changed, wherein the scanning schedule as changed defines a different temporal pattern of scanning windows that are separated by one or more scanning intervals.
23. The non-transitory computer readable storage medium of claim 22 , wherein the instructions to scan the one or more channels for an advertisement notice transmitted by the IMD in accordance with the scanning schedule comprises instructions to:
set a scanning interval timer to at least two different scanning intervals based on the scanning schedule; and
set a window duration timer that defines a duration of each of the scanning windows.
24. The non-transitory computer readable storage medium of claim 23 , wherein the instructions to set the scanning interval timer comprises instructions to:
set the scanning interval timer to a first scanning interval based on the scanning schedule; and
set the scanning interval timer to a second scanning interval based on the scanning schedule, in response to determining that the scanning interval timer, which had been set to the first scanning interval, timed out without a valid advertisement notice being received by the EI from the IMD.