Beacon-Enabled Communications for Variable Payload Transfers

• US 20120263189A1
• Filed: 04/10/2012
• Published: 10/18/2012
• Est. Priority Date: 04/18/2011
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Vijayasankar, Kumaran, Vedantham, Ramanuja, Varadarajan, Badri N., Dabak, Anand G.
• Granted Patent: US 11,368,190 B2
• Time in Patent Office: Days
• US Class Current: 370/436
• CPC Class Codes: H04B 3/544 Setting up communications; Call and signalling arrangements
• CPC Class Codes: H04L 25/0272 Arrangements for coupling to multiple lines, e.g. for differential transmission
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals

Abstract

Systems and methods for designing, using, and/or implementing beacon-enabled communications for variable payload transfers are described. In various embodiments, these systems and methods may be applicable to power line communications (PLC). For example, a method may include implementing a superframe having a plurality of beacon slots, a plurality of intermediate slots following the beacon slots, and a poll-based Contention Free Period (CFP) slot following the intermediate slots. Each of the beacon slots and each of the intermediate slots may correspond to a respective one of a plurality of frequency subbands, and the poll-based CFP slot may correspond to a combination of the plurality of frequency subbands. The method may also include receiving a poll request over a first of the plurality of frequency subbands during the poll-based CFP slot, and then transmitting a data packet over a second of the plurality of frequency subbands during the poll-based CFP slot.

Claims

1. A method comprising:

performing, by a communication device,

implementing a superframe structure having a plurality of beacon slots, a plurality of intermediate slots following the plurality of beacon slots, and a poll-based Contention Free Period (CFP) slot following the plurality of intermediate slots, each of the plurality of beacon slots and each of the plurality of intermediate slots corresponding to a respective one of a plurality of frequency subbands, and the poll-based CFP slot corresponding to a combination of the plurality of frequency subbands;

receiving a poll request over a first of the plurality of frequency subbands during the poll-based CFP slot; and

in response to the poll request, transmitting a data packet over a second of the plurality of frequency subbands during the poll-based CFP slot.

2. The method of claim 1, further comprising:

performing, by the communication device,

in response to transmitting the data packet, receiving an acknowledgement message over the first of the plurality of frequency subbands.

3. The method of claim 1, further comprising:

performing, by the communication device,

adding an indication to the data packet of one or more outstanding data packets; and

transmitting the one or more outstanding data packets over the second of the plurality of frequency subbands following the data packet during the poll-based CFP slot.

4. The method of claim 3, wherein transmitting the one or more outstanding data packets includes transmitting the one or more outstanding data packets without exceeding a maximum number of packets transmittable in response to the poll request.

5. The method of claim 3, wherein transmitting the one or more outstanding data packets includes transmitting the one or more outstanding data packets without exceeding a maximum transmission duration.

6. The method of claim 1, further comprising:

performing, by the communication device,

detecting at least one beacon during one of the plurality of beacon slots, the detected beacon having been transmitted over a respective frequency subband;

creating a downlink subband report based, at least in part, upon the detected beacon;

transmitting the downlink subband report over each of the plurality of frequency subbands during respective intermediate slots; and

receiving a subband allocation message, the subband allocation message identifying the first of the plurality of frequency subbands as suitable for subsequent downlink communications and identifying the second of the plurality of frequency subbands as suitable for subsequent uplink communications.

7. The method of claim 1, wherein the intermediate slots are Contention Access Period (CAP) slots during which one or more other communications devices are allowed to compete with the communication device for access to a communication medium.

8. The method of claim 7, further comprising:

performing, by the communication device,

receiving data over the first of the plurality of frequency subbands during a first CAP slot corresponding to the first frequency subband; and

transmitting an acknowledgement message over the second of the plurality of frequency subbands during the first CAP slot.

9. The method of claim 7, further comprising:

performing, by the communication device,

transmitting data over the second of the plurality of frequency subbands during a second CAP slot corresponding to the second frequency subband; and

receiving an acknowledgement message over the first of the plurality of frequency subbands during the second CAP slot.

10. The method of claim 1, wherein the intermediate slots are Discovery Phase (DP) slots during which the communication device abstains from transmitting data packets, the presence or absence of DP slots indicated in one or more beacons received over one or more of the plurality of beacon slots.

11. The method of claim 10, wherein the presence or absence of DP slots implements access control to limit a number of communication devices capable of joining a network.

12. A PLC device, comprising:

a processor; and

a memory coupled to the processor, the memory configured to store program instructions executable by the processor to cause the PLC device to;

implement a superframe structure having a plurality of beacon slots, a plurality of Contention Access Period (CAP) slots following the plurality of beacon slots, and a poll-based Contention Free Period (CFP) slot following the plurality of CAP slots, each of the plurality of beacon slots and each of the plurality of CAP slots corresponding to a respective one of a plurality of frequency subbands, and the poll-based CFP slot corresponding to a combination of the plurality of frequency subbands;

transmit a poll request over a first of the plurality of frequency subbands during the poll-based CFP slot; and

in response to the poll request, receive a data packet over a second of the plurality of frequency subbands during the poll-based CFP slot.

13. The PLC device of claim 12, wherein the processor includes a digital signal processor (DSP), an application specific integrated circuit (ASIC), a system-on-chip (SoC) circuit, a field-programmable gate array (FPGA), a microprocessor, or a microcontroller.

14. The PLC device of claim 12, wherein the program instructions are executable by the processor to further cause the PLC device to:

in response to having received the data packet, transmit an acknowledgement message over the first of the plurality of frequency subbands during the poll-based CFP slot.

15. The PLC device of claim 12, wherein the program instructions are executable by the processor to further cause the PLC device to:

transmit a plurality of beacons, each of the plurality of beacons transmitted over a corresponding one of the plurality of beacon slots;

receive a downlink subband report during at least one of the plurality of CAP slots; and

transmit a subband allocation message over the first of the plurality of frequency subbands during at least one of;

one of the plurality of CAP slots or the poll-based CFP slot, the subband allocation message identifying the first of the plurality of frequency subbands as suitable for subsequent downlink communications and identifying the second of the plurality of frequency subbands as suitable for subsequent uplink communications.

16. The PLC device of claim 12, wherein the program instructions are executable by the processor to further cause the PLC device to:

transmit data over the first of the plurality of frequency subbands during a first CAP slot corresponding to the first frequency subband; and

receive an acknowledgement message over the second of the plurality of frequency subbands during the first CAP slot.

17. The PLC device of claim 12, wherein the program instructions are executable by the processor to further cause the PLC device to:

receive data over the second of the plurality of frequency subbands during a second CAP slot corresponding to the second frequency subband; and

transmit an acknowledgement message over the first of the plurality of frequency subbands during the second CAP slot.

18. The PLC device of claim 12, wherein PLC device is a PLC data concentrator or router.

19. A non-transitory electronic storage medium having program instructions stored thereon that, upon execution by a processor within a power line communication (PLC) data concentrator, cause the PLC data concentrator to:

implement a first superframe structure having a plurality of beacon slots, a plurality of Discovery Phase (DP) slots following the plurality of beacon slots, and a poll-based Contention Free Period (CFP) slot following the plurality of DP slots, each of the plurality of beacon slots and each of the plurality of DP slots corresponding to a respective one of a plurality of frequency subbands, and the poll-based CFP slot corresponding to a combination of the plurality of frequency subbands;

transmit a poll request over a first of the plurality of frequency subbands during the poll-based CFP slot; and

in response to the poll request, receive a data packet over a second of the plurality of frequency subbands during the poll-based CFP slot.

20. The electronic storage medium of claim 19, wherein the program instructions, upon execution by the processor, further cause the PLC data concentrator to:

implement a second superframe structure having the plurality of beacon slots and the poll-based CFP following the plurality of beacon slots, the second superframe structure excluding the plurality of DP slots; and

perform one of;

(a) in response to one or more PLC devices being allowed to join the PLC data concentrator, follow the first superframe structure;

or (b) in response to one or more PLC devices not being allowed to join the PLC data concentrator, follow the second superframe structure.