Robust channel reservation on a shared communication medium

1. A communication method, comprising:

contending for access to a communication medium shared between a competing Radio Access Technology (RAT) and a primary RAT;

encoding a first portion of a channel reservation message defined by the competing RAT with a transmission opportunity duration associated with the primary RAT;

encoding a second portion of the channel reservation message with the transmission opportunity duration;

encoding the second portion of the channel reservation message with an operator identifier associated with the primary RAT; and

transmitting, over the communication medium, the channel reservation message including the first and second portions to reserve the communication medium based on the contending,

wherein the transmission opportunity duration in the first portion is decodable by devices of the competing RAT but is not decodable by devices of the primary RAT,

wherein the transmission opportunity duration in the second portion is decodable by the devices of the competing RAT and by the devices of the primary RAT, and

wherein the encoding of the second portion comprises:

selecting a duration for the channel reservation message based on the transmission opportunity duration, the operator identifier, or a combination thereof; and

setting a length field of the channel reservation message based on the selected duration.

2. The method of claim 1 , wherein the second portion corresponds to a Physical (PHY) header of the channel reservation message.

3. The method of claim 2 , wherein the first portion corresponds to a Medium Access Control (MAC) header of the channel reservation message.

4. The method of claim 2 , wherein the encoding of the second portion comprises encoding one or more rate, length, or reserved bits in a Legacy Signal (L-SIG) field of a Physical Layer Convergence Protocol (PLCP) header.

5. The method of claim 1 , wherein the operator identifier corresponds to a Public Land Mobile Network Identifier (PLMN ID).

6. The method of claim 1 , wherein the selecting is further based on a predetermined set of one or more values of the length field that identify an association with the primary RAT.

7. The method of claim 1 , wherein the encoding of the second portion comprises:

selecting a transmission rate for the channel reservation message based on one of the transmission opportunity duration or the operator identifier;

setting a rate field of the channel reservation message based on the selected transmission rate;

selecting the duration for the channel reservation message based on the other of the transmission opportunity duration or the operator identifier; and

setting the length field of the channel reservation message based on the selected duration.

8. The method of claim 7 , wherein the encoding of the second portion further comprises setting a reserved field of the channel reservation message based on the one of the transmission opportunity duration or the operator identifier.

9. The method of claim 1 , wherein the channel reservation message comprises a Clear-to-Send-to-Self (CTS2S) message defined by the competing RAT, a Request-to-Send (RTS) message defined by the competing RAT, or a Clear-to-Send (CTS) message defined by the competing RAT.

10. The method of claim 1 , wherein the communication medium corresponds to an unlicensed radio frequency band.

11. The method of claim 1 , wherein:

the competing RAT comprises Wi-Fi technology; and

the primary RAT comprises Long Term Evolution (LTE) technology.

12. The method of claim 1 , wherein the devices of the primary RAT ignore any channel reservation message defined by the primary RAT.

13. A communication apparatus, comprising:

at least one processor;

at least one memory, the at least one processor and the at least one memory being configured to:

contend for access to a communication medium shared between a competing Radio Access Technology (RAT) and a primary RAT,

encode a first portion of a channel reservation message defined by the competing RAT with a transmission opportunity duration associated with the primary RAT,

encode the second portion of the channel reservation message with an operator identifier associated with the primary RAT, and

encode a second portion of the channel reservation message with the transmission opportunity duration; and

a transceiver configured to transmit, over the communication medium, the channel reservation message including the first and second portions to reserve the communication medium based on the contending,

wherein the transmission opportunity duration in the first portion is decodable by devices of the competing RAT but is not decodable by devices of the primary RAT,

wherein the transmission opportunity duration in the second portion is decodable by the devices of the competing RAT and by the devices of the primary RAT, and

wherein the at least one processor and the at least one memory are configured to encode the second portion by:

selecting a duration for the channel reservation message based on the transmission opportunity duration, the operator identifier, or a combination thereof; and

setting a length field of the channel reservation message based on the selected duration.

14. The apparatus of claim 13 , wherein the second portion corresponds to a Physical (PHY) header of the channel reservation message.

15. The apparatus of claim 14 , wherein the first portion corresponds to a Medium Access Control (MAC) header of the channel reservation message.

16. The apparatus of claim 14 , wherein the at least one processor and the at least one memory are configured to encode the second portion by encoding one or more rate, length, or reserved bits in a Legacy Signal (L-SIG) field of a Physical Layer Convergence Protocol (PLCP) header.

17. The apparatus of claim 13 , wherein the at least one processor and the at least one memory are configured to encode the second portion by:

selecting a transmission rate for the channel reservation message based on one of the transmission opportunity duration or the operator identifier;

setting a rate field of the channel reservation message based on the selected transmission rate;

selecting the duration for the channel reservation message based on the other of the transmission opportunity duration or the operator identifier; and

setting the length field of the channel reservation message based on the selected duration.

18. The apparatus of claim 13 , wherein the devices of the primary RAT ignore any channel reservation message defined by the primary RAT.

19. The apparatus of claim 13 , wherein the at least one processor and the at least one memory are configured to select the duration for the channel message further based on a predetermined set of one or more values of the length field that identify an association with the primary RAT.

20. The apparatus of claim 13 , wherein the channel reservation message comprises a Clear-to-Send-to-Self (CTS2S) message defined by the competing RAT, a Request-to-Send (RTS) message defined by the competing RAT, or a Clear-to-Send (CTS) message defined by the competing RAT.

21. The apparatus of claim 13 , wherein the communication medium corresponds to an unlicensed radio frequency band.

22. A communication apparatus, comprising:

means for contending for access to a communication medium shared between a competing Radio Access Technology (RAT) and a primary RAT;

means for encoding a first portion of a channel reservation message defined by the competing RAT with a transmission opportunity duration associated with the primary RAT;

means for encoding a second portion of the channel reservation message with the transmission opportunity duration;

means for encoding the second portion of the channel reservation message with an operator identifier associated with the primary RAT; and

means for transmitting, over the communication medium, the channel reservation message including the first and second portions to reserve the communication medium based on the contending,

wherein the transmission opportunity duration in the first portion is decodable by devices of the competing RAT but is not decodable by devices of the primary RAT,

wherein the transmission opportunity duration in the second portion is decodable by the devices of the competing RAT and by the devices of the primary RAT, and

wherein the means for encoding of the second portion comprises:

selects a duration for the channel reservation message based on the transmission opportunity duration, the operator identifier, or a combination thereof, and

sets a length field of the channel reservation message based on the selected duration.

23. The apparatus of claim 22 , wherein the devices of the primary RAT ignore any channel reservation message defined by the primary RAT.

24. The apparatus of claim 17 , the at least one processor and the at least one memory are further configured to encode the second portion by setting a reserved field of the channel reservation message based on the one of the transmission opportunity duration or the operator identifier.

25. The apparatus of claim 22 ,

wherein the second portion corresponds to a Physical (PHY) header of the channel reservation message, and

wherein the first portion corresponds to a Medium Access Control (MAC) header of the channel reservation message.

26. The apparatus of claim 22 , wherein the means for encoding the second portion encodes one or more rate, length, or reserved bits in a Legacy Signal (L-SIG) field of a Physical Layer Convergence Protocol (PLCP) header.

27. The apparatus of claim 22 , wherein the means for selecting the duration selects the duration for the channel reservation message further based on a predetermined set of one or more values of the length field that identify an association with the primary RAT.

28. The apparatus of claim 22 , wherein the means for encoding the second portion

selects a transmission rate for the channel reservation message based on one of the transmission opportunity duration or the operator identifier,

sets a rate field of the channel reservation message based on the selected transmission rate,

selecting the duration for the channel reservation message based on the other of the transmission opportunity duration or the operator identifier, and

setting the length field of the channel reservation message based on the selected duration.

29. A non-transitory computer-readable medium comprising code, which, when executed by at least one processor, causes the at least one processor to perform operations for communication, the non-transitory computer-readable medium comprising:

code for contending for access to a communication medium shared between a competing Radio Access Technology (RAT) and a primary RAT;

code for encoding a first portion of a channel reservation message defined by the competing RAT with a transmission opportunity duration associated with the primary RAT;

code for encoding a second portion of the channel reservation message with the transmission opportunity duration;

code for encoding the second portion of the channel reservation message with an operator identifier associated with the primary RAT; and

code for transmitting, over the communication medium, the channel reservation message including the first and second portions to reserve the communication medium based on the contending,

wherein the transmission opportunity duration in the first portion is decodable by devices of the competing RAT but is not decodable by devices of the primary RAT,

wherein the transmission opportunity duration in the second portion is decodable by the devices of the competing RAT and by the devices of the primary RAT, and

wherein the code for encoding of the second portion comprises:

code for selecting a duration for the channel reservation message based on the transmission opportunity duration, the operator identifier, or a combination thereof; and

code for setting a length field of the channel reservation message based on the selected duration.

30. The non-transitory computer-readable medium of claim 29 , wherein the devices of the primary RAT ignore any channel reservation message defined by the primary RAT.

31. The non-transitory computer-readable medium of claim 29 ,

wherein the second portion corresponds to a Physical (PHY) header of the channel reservation message, and

wherein the first portion corresponds to a Medium Access Control (MAC) header of the channel reservation message.

32. The non-transitory computer-readable medium of claim 29 , wherein the code for encoding the second portion comprises code for encoding one or more rate, length, or reserved bits in a Legacy Signal (L-SIG) field of a Physical Layer Convergence Protocol (PLCP) header.

33. The non-transitory computer-readable medium of claim 29 , wherein the code for selecting the duration selects the duration for the channel reservation message further based on a predetermined set of one or more values of the length field that identify an association with the primary RAT.

34. The non-transitory computer-readable medium of claim 29 , wherein the code for encoding of the second portion comprises:

code for selecting a transmission rate for the channel reservation message based on one of the transmission opportunity duration or the operator identifier;

code for setting a rate field of the channel reservation message based on the selected transmission rate;

code for selecting the duration for the channel reservation message based on the other of the transmission opportunity duration or the operator identifier; and

code for setting the length field of the channel reservation message based on the selected duration.