Techniques for supporting multiple bandwidth modes

1. A method for wireless communication, comprising:

signaling an association response frame including an operating mode notification (OMN) element that indicates support by a wireless device for a first bandwidth mode and a second bandwidth mode and that indicates a number of supported multiple-input, multiple-output (MIMO) spatial streams, wherein the first bandwidth mode utilizes a single channel and the second bandwidth mode utilizes channel bonding between a plurality of channels;

switching a current bandwidth mode of the wireless device from one of the bandwidth modes to the other of the bandwidth modes;

adjusting a number of MIMO spatial streams supported by the wireless device in response to the switching; and

adjusting a number of receive chains used for the plurality of channels based on a listening mode or a data demodulation mode.

2. The method of claim 1 , wherein:

switching the current bandwidth mode of the wireless device comprises switching from the first bandwidth mode to the second bandwidth mode; and

adjusting the number of MIMO spatial streams comprises reducing the number of MIMO spatial streams supported by the wireless device.

3. The method of claim 1 , wherein:

switching the current bandwidth mode of the wireless device comprises switching from the second bandwidth mode to the first bandwidth mode; and

adjusting the number of MIMO spatial streams comprises increasing the number of MIMO spatial streams supported by the wireless device.

4. The method of claim 1 , wherein the number of MIMO spatial streams is adjusted in proportion to an increase or decrease in bandwidth associated with switching the current bandwidth mode of the wireless device.

5. The method of claim 1 , further comprising:

adjusting sampling rates of one or more analog-to-digital converters (ADCs) of the wireless device in response to the switching.

6. The method of claim 5 , wherein:

adjusting the sampling rates of the one or more ADCs comprises doubling the sampling rates in response to switching the current bandwidth mode from the first bandwidth mode to the second bandwidth mode; and

adjusting the sampling rates of the one or more ADCs comprises halving the sampling rates in response to switching the current bandwidth mode from the second bandwidth mode to the first bandwidth mode.

7. The method of claim 1 , wherein:

switching the current bandwidth mode of the wireless device comprises adjusting a number of synthesizers used by the wireless device.

8. The method of claim 1 , wherein:

adjusting the number of receive chains comprises one of: increasing a number of receive chains used for a primary channel of the plurality of channels and decreasing a number of receive chains used for a secondary channel of the plurality of channels; and

decreasing the number of receive chains used for the primary channel and increasing the number of receive chains used for the secondary channel.

9. The method of claim 1 , further comprising:

receiving a data packet at the wireless device wherein switching the current bandwidth mode occurs in one of a symbol after the wireless device determines a packet format of the data packet and in a symbol used for updating a gain level.

10. The method of claim 1 , wherein a management message indicates the listening mode to a physical layer (PHY), further comprising:

adjusting a configuration of a receiver of the wireless device for reception of an expected data packet type based on the management message.

11. The method of claim 1 , wherein the wireless device is a first wireless device, further comprising:

determining that an acknowledgement having a bandwidth equal to or less than a bandwidth of the single channel is expected at the first wireless device from a second wireless device; and

adjusting a number of receive chains used for the single channel in response to the determination and based on a management message to a physical layer (PHY) that indicates a parameter from the group consisting of: the number of receive chains used for the single channel and a number of frequency segments associated with a listen mode.

12. The method of claim 1 , wherein:

the OMN element indicates a parameter indicating an operating bandwidth.

13. An apparatus for wireless communication, comprising:

a transceiver to signal an association response frame including an operating mode notification (OMN) element that indicates support by a wireless device for a first bandwidth mode and a second bandwidth mode and that indicates a number of supported multiple-input, multiple-output (MIMO) spatial streams, wherein the first bandwidth mode utilizes a single channel and the second bandwidth mode utilizes channel bonding between a plurality of channels;

a bandwidth selector to switch a current bandwidth mode of the wireless device from one of the bandwidth modes to the other of the bandwidth modes and to adjust a number of receive chains used for the plurality of channels based on a listening mode or a data demodulation mode; and

a spatial stream component to adjust a number of MIMO spatial streams supported by the wireless device in response to the switching.

14. The apparatus of claim 13 , wherein:

switching the current bandwidth mode of the wireless device comprises switching from the first bandwidth mode to the second bandwidth mode; and

adjusting the number of MIMO spatial streams comprises reducing the number of MIMO spatial streams supported by the wireless device.

15. The apparatus of claim 13 , wherein:

switching the current bandwidth mode of the wireless device comprises switching from the second bandwidth mode to the first bandwidth mode; and

adjusting the number of MIMO spatial streams comprises increasing the number of MIMO spatial streams supported by the wireless device.

16. The apparatus of claim 13 , wherein the number of MIMO spatial streams is adjusted in proportion to an increase or decrease in bandwidth associated with switching the current bandwidth mode of the wireless device.

17. The apparatus of claim 13 , wherein the bandwidth selector is further to adjust sampling rates of one or more analog-to-digital converters (ADCs) of the wireless device in response to the switching.

18. The apparatus of claim 17 , wherein the bandwidth selector is further to adjust a number of synthesizers used by the wireless device in response to the switching.

19. The apparatus of claim 13 , wherein the transceiver is further to receive a data packet at the wireless device, and wherein switching the current bandwidth mode occurs in one of a symbol after the wireless device determines a packet format of the data packet and in a symbol used for updating a gain level.

20. The apparatus of claim 13 , wherein the bandwidth selector is further to indicate the listening mode to a physical layer of the wireless device via a management message, wherein the transceiver is adjusted for reception of an expected data packet type based on the management message.

21. The apparatus of claim 13 , wherein the wireless device is a first wireless device, and wherein the bandwidth selector is further to:

determine that an acknowledgement having a bandwidth equal to or less than a bandwidth of the single channel is expected at the first wireless device from a second wireless device; and

adjust a number of receive chains used for the single channel in response to the determination and based on a management message to a physical layer (PHY) that indicates a parameter from the group consisting of: the number of receive chains used for the single channel and a number of frequency segments associated with the listen mode.

22. The apparatus of claim 13 , wherein:

the OMN element indicates a parameter indicating an operating bandwidth of the single channel and the number of MIMO spatial streams supported by the wireless device.

23. An apparatus for wireless communication, comprising:

means for signaling an association response frame including an operating mode notification (OMN) element that indicates support by a wireless device for a first bandwidth mode and a second bandwidth mode and that indicates a number of supported multiple-input, multiple-output (MIMO) spatial streams, wherein the first bandwidth mode utilizes a single channel and the second bandwidth mode utilizes channel bonding between a plurality of channels;

means for switching a current bandwidth mode of the wireless device from one of the bandwidth modes to the other of the bandwidth modes;

means for adjusting a number of MIMO spatial streams supported by the wireless device in response to the switching and

means for adjusting a number of receive chains used for the plurality of channels based on a listening mode or a data demodulation mode.

24. The apparatus of claim 23 , further comprising:

means for adjusting sampling rates of one or more analog-to-digital converters (ADCs) of the wireless device in response to the switching.

25. The apparatus of claim 23 , wherein the means for switching the current bandwidth mode of the wireless device comprises:

means for adjusting a number of synthesizers used by the wireless device.

26. A non-transitory computer-readable medium storing computer-executable code for wireless communication, the code executable by a processor to cause a wireless device to:

signal an association response frame including an operating mode notification (OMN) element that indicates support by a wireless device for a first bandwidth mode and a second bandwidth mode and that indicates a number of supported multiple-input, multiple-output (MIMO) spatial streams, wherein the first bandwidth mode utilizes a single channel and the second bandwidth mode utilizes channel bonding between a plurality of channels;

switch a current bandwidth mode of the wireless device from one of the bandwidth modes to the other of the bandwidth modes;

adjust a number of MIMO spatial streams supported by the wireless device in response to the switching and

adjust a number of receive chains used for the plurality of channels based on a listening mode or a data demodulation mode.