Systems and methods for self-formation and self-management of full-duplex communication networks
Disclosed herein are systems and methods for self-formation and self-management of full-duplex communication networks. In an embodiment, a communication device determines whether there is an available self-assignable device-data time slot. If there is, the device selects an available time slot for outbound transmissions, updates its network-status table to associate the selected time slot with a device identifier of the communication device, and transmits outbound device data during the selected time slot of at least one ensuing frame. The device also, during each of a plurality of ensuing frames, makes a determination as to whether to transmit a maintenance packet during a shared time slot of the current frame. If the determination is made in the affirmative, the device transmits such a packet during that shared time slot. Each such packet contains at least a subset of the network-status table.
1. A method carried out by a communication device that comprises data storage and a communication interface, the method comprising:
determining whether or not there is at least one available self-assignable device-data time slot among N self-assignable device-data time slots in a frame structure, the frame structure further comprising a shared network-self-administration time slot; and
if there is at least one available device-data time slot, then:
selecting an available device-data time slot for outbound transmissions;
updating a network-status table maintained in the data storage to include an association between the selected device-data time slot and a device identifier of the communication device;
transmitting outbound device data via the communication interface during the selected device-data time slot of at least one ensuing frame; and
during each of a plurality of ensuing frames, making a determination as to whether to transmit a maintenance packet during the shared network-self-administration time slot of the current frame, and transmitting such a packet via the communication interface during said shared time slot if the determination is made in the affirmative, each such maintenance packet containing at least a subset of the network-status table.
2. The method of claim 1 , wherein:
the communication device further comprises a user interface, wherein the user interface comprises at least one microphone for receiving audio and at least one speaker for outputting audio;
the outbound data comprises digital-audio data corresponding to audio received via the user interface; and
the method further comprises:
outputting, via the user interface, audio corresponding to any digital-audio data received via the communication interface during any one or more of the N device-data time slots other than the selected time slot.
3. The method of claim 1 , wherein:
the communication device is communicatively connected to at least one sensor; and
the device data comprises sensor data from the at least one sensor.
4. The method of claim 1 , wherein determining whether or not there is at least one available self-assignable device-data time slot among the N self-assignable device-data time slots in the frame structure comprises:
receiving and analyzing a maintenance packet sent by another communication device during the shared network-self-administration time slot of a given frame, wherein the received maintenance packet conveys a current status of assignment of device-data time slots to communication devices.
5. The method of claim 4 , further comprising updating the stored network-status table based on the received maintenance packet.
6. The method of claim 1 , wherein determining whether or not there is at least one available self-assignable device-data time slot among the N self-assignable device-data time slots in the frame structure comprises:
tracking whether any device data is received via the communication interface during any one or more of the N device-data time slots other than the selected time slot.
7. The method of claim 6 , further comprising updating the stored network-status table based on header data associated with device data received during one or more of the N device-data time slots other than the selected time slot.
8. The method of claim 1 , further comprising using data received during a device-data time slot other than the selected time slot as a timing reference.
9. The method of claim 8 , further comprising identifying the other device-data time slot for use as the timing reference based on a device ID of a device assigned to transmit during the other time slot.
10. The method of claim 9 , wherein the communication device had inserted the device ID of the device assigned to transmit during the other time slot into the stored network-status table responsive to receiving the device ID in header data associated with device data received during the other time slot.
11. The method of claim 9 , wherein the communication device had inserted the device ID of the device assigned to transmit during the other time slot into the stored network-status table responsive to receiving the device ID in a maintenance packet during the shared network-self-administration time slot.
12. The method of claim 1 , wherein each transmitted maintenance packet includes the subset of the network-status table corresponding to communication devices from which device data has been received within a preceding first timeout period.
13. The method of claim 12 , further comprising:
resetting the first timeout period for each communication device upon receipt of device data from the respective communication device; and
dropping communication devices from being listed in outgoing maintenance packets upon expiration of the first timeout period for the respective communication device.
14. The method of claim 12 , wherein the network-status table further comprises one or more communication devices listed on one or more maintenance packets received during the shared network-self-administration time slot of one or more frames within a preceding second timeout period.
15. The method of claim 14 , further comprising:
resetting the second timeout period for each communication device upon receipt of each maintenance packet listing the respective communication device; and
dropping communication devices from the network-status table upon expiration of the second timeout period for the respective communication device.
16. The method of claim 1 , further comprising operating in a listen-only mode if there is not at least one available device-data time slot.
17. The method of claim 16 , further comprising:
while operating in the listen-only mode, determining that a device-data time slot has become available, and responsively selecting that time slot for outbound transmissions.
18. The method of claim 17 , further comprising:
detecting a collision with at least one other device in that device-data time slot, and responsively executing a time-slot-collision-arbitration protocol.
19. The method of claim 18 , wherein executing the time-slot-collision-arbitration protocol comprises deciding whether to maintain a claim on that device-data time slot or to cede the device-data time slot for use by another device based on a comparison of the device identifier of the communication device with respective device identifiers of each of the at least one other device.
20. The method of claim 1 , wherein the plurality of ensuing frames are those ensuing frames that correspond to an expiration of a maintenance-packet-transmission timer maintained by the communication device.
21. The method of claim 1 , wherein making the maintenance-packet determination comprises randomly determining whether or not to transmit a maintenance packet during the shared network-self-administration time slot of the current frame.
22. The method of claim 21 , wherein randomly determining whether or not to transmit a maintenance packet during the shared network-self-administration time slot of the current frame comprises basing the decision on a current network-occupancy level.
23. The method of claim 1 , further comprising detecting a collision with at least one other device in the selected device-data time slot, and responsively executing a time-slot-collision-arbitration protocol.
24. The method of claim 23 , wherein executing the time-slot-collision-arbitration protocol comprises deciding whether to maintain a claim on the selected device-data time slot or to cede the selected device-data time slot for use by another device based on a comparison of the device identifier of the communication device with respective device identifiers of each of the at least one other device.
25. A communication device comprising:
a communication interface;
a processor; and
data storage containing instructions executable by the processor for carrying out a set of functions, wherein the set of functions comprises:
determining whether or not there is at least one available self-assignable device-data time slot among N self-assignable device-data time slots in a frame structure, the frame structure further comprising a shared network-self-administration time slot; and
if there is at least one available device-data time slot, then:
selecting an available device-data time slot for outbound transmissions;
updating a network-status table maintained in the data storage to include an association between the selected device-data time slot and a device identifier of the communication device;
transmitting outbound device data via the communication interface during the selected device-data time slot of at least one ensuing frame; and
during each of a plurality of ensuing frames, making a determination as to whether to transmit a maintenance packet during the shared network-self-administration time slot of the current frame, and transmitting such a packet via the communication interface during said shared time slot if the determination is made in the affirmative, each such maintenance packet containing at least a subset of the network-status table.
26. The communication device of claim 25 , further comprising a user interface, wherein the outbound data comprises digital-audio data corresponding to audio received via the user interface, and wherein the set of functions further comprises:
outputting, via the user interface, audio corresponding to any digital-audio data received via the communication interface during any one or more of the N device-data time slots other than the selected time slot.
27. The communication device of claim 26 , wherein the user interface comprises at least one microphone for receiving audio and at least one speaker for outputting audio.
28. The communication device of claim 25 , wherein:
the communication device is communicatively connected to at least one sensor; and
the device data comprises sensor data from the at least one sensor.
29. A computer-readable medium containing instructions executable by a processor for carrying out a set of functions, wherein the set of functions comprises:
determining whether or not there is at least one available self-assignable device-data time slot among N self-assignable device-data time slots in a frame structure, the frame structure further comprising a shared network-self-administration time slot; and
if there is at least one available device-data time slot, then:
selecting an available device-data time slot for outbound transmissions;
updating a network-status table maintained in data storage to include an association between the selected device-data time slot and a device identifier of a communication device;
transmitting outbound device data via a communication interface during the selected device-data time slot of at least one ensuing frame; and
during each of a plurality of ensuing frames, making a determination as to whether to transmit a maintenance packet during the shared network-self-administration time slot of the current frame, and transmitting such a packet via the communication interface during said shared time slot if the determination is made in the affirmative, each such maintenance packet containing at least a subset of the network-status table.