SPATIAL MULTIPLEXING POWER SAVE LEARNING MODE

• US 20160360489A1
• Filed: 06/03/2016
• Published: 12/08/2016
• Est. Priority Date: 06/05/2015
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: ZENG, Zheng, BOODANNAVAR, Veerendra, CHHABRA, Kapil
• Granted Patent: US 9,930,561 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 28/0231 based on communication conditions dynamic wireless traffic scheduling definition based on channel quality criteria H04W72/54
• CPC Class Codes: H04W 52/0235 where the received signal is a power saving command
• CPC Class Codes: H04W 52/0261 managing power supply demand, e.g. depending on battery level
• CPC Class Codes: H04W 52/0274 by switching on or off the equipment or parts thereof
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: Y02B 70/00 Technologies for an efficient end-user side electric power management and consumption
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Apparatus and methods for configuring wireless circuitry of a wireless communication device associated with a wireless local area network (WLAN) access point (AP) to use a reduced power consumption mode are disclosed. While associated with a multiple-input multiple-output (MIMO) WLAN AP and operating in a MIMO mode that includes at least two spatial streams for communication with multiple radio frequency (RF) receive chains active, the wireless communication device transmits a message indicating a request to use a spatial multiplexing power save (SMPS) mode that supports only one spatial stream and requires only a single active RF receive chain. The wireless communication device monitors packets received from the WLAN AP after a guard interval following the request and only switches to the SMPS mode when all packets received after the guard interval use only one spatial stream.

Claims

1. A method for configuring wireless circuitry in a wireless communication device, the method comprising:

by the wireless communication device;

transmitting a message indicating a request to operate in a spatial multiplexing power save (SMPS) mode to a wireless local area network (WLAN) access point (AP) associated with the wireless communication device, the SMPS mode supporting only one spatial stream in a single-input single-output (SISO) mode;

monitoring packets received from the WLAN AP after transmitting the message and following a guard interval;

maintaining, in an operational state, the wireless circuitry configured to use a multiple-input multiple-output (MIMO) mode that includes at least two spatial streams for communication between the wireless communication device and the WLAN AP, when receiving at least one packet from the WLAN AP that uses at least two spatial streams; and

configuring the wireless circuitry to use the SISO mode, which includes only a single spatial stream for communication between the wireless communication device and the WLAN AP, when all packets received from the WLAN AP after the guard interval use only one spatial stream, and the number of packets received equals or exceeds a minimum successive packet threshold.

2. The method of claim 1, wherein the minimum successive packet threshold comprises at least one hundred successive packets received after the guard interval, and wherein the guard interval spans at least one hundred milliseconds.

3. The method of claim 1, wherein configuring the wireless circuitry to use the MIMO mode comprises enabling at least two radio frequency (RF) receive chains to process the at least two spatial streams.

4. The method of claim 1, wherein configuring the wireless circuitry to use the SISO mode comprises enabling only one radio frequency (RF) receive chain to process the single spatial stream received from the WLAN AP.

5. The method of claim 4, wherein configuring the wireless circuity to use the SISO mode further comprises enabling only one RF transmit chain for communication to the WLAN AP.

6. The method of claim 1, wherein the message indicating the request to operate in the SMPS mode comprises an SMPS request in accordance with an 802.11n wireless communication protocol.

7. The method of claim 1, further comprising:

by the wireless communication device;

retransmitting the message indicating the request to operate in the SMPS mode up to a maximum repeat request number of times; and

maintaining, in the operational state, the wireless circuitry configured to use the MIMO mode that includes at least two spatial streams for communication between the wireless communication device and the WLAN AP when receiving at least one packet from the WLAN AP that uses at least two spatial streams after a corresponding guard interval following each retransmitted message.

8. A wireless communication device comprising:

wireless circuitry including a plurality of radio frequency (RF) receive chains;

one or more processors coupled to the wireless circuitry; and

a memory coupled to the one or more processors,

wherein the one or more processors are configured to execute computer-executable instructions stored within the memory to cause the wireless communication device to;

transmit a message indicating a request to operate in a spatial multiplexing power save (SMPS) mode to a wireless local area network (WLAN) access point (AP) associated with the wireless communication device, the SMPS mode supporting only one spatial stream in a single-input single-output (SISO) mode;

monitor packets received from the WLAN AP after transmitting the message and following a guard interval;

maintain, in an operational state, the wireless circuitry configured to use a multiple-input multiple-output (MIMO) mode that includes at least two spatial streams for communication between the wireless communication device and the WLAN AP, when receiving at least one packet from the WLAN AP that uses at least two spatial streams; and

configure the wireless circuitry to use the SISO mode, which includes only a single spatial stream for communication between the wireless communication device and the WLAN AP, when all packets received from the WLAN AP after the guard interval use only one spatial stream, and the number of packets received equals or exceeds a minimum successive packet threshold.

9. The wireless communication device of claim 8, wherein the minimum successive packet threshold comprises at least one hundred successive packets received after the guard interval, and wherein the guard interval spans at least one hundred milliseconds.

10. The wireless communication device of claim 8, wherein the wireless communication device configures the wireless circuitry to use the MIMO mode by enabling at least two least two radio frequency (RF) receive chains to process the at least two spatial streams.

11. The wireless communication device of claim 8, wherein the wireless communication device configures the wireless circuitry to use the SISO mode by enabling only one radio frequency (RF) receive chain to process the single spatial stream received from the WLAN AP.

12. The wireless communication device of claim 11, wherein the wireless communication device configures the wireless circuitry to use the SISO mode further by enabling only one RF transmit chain for communication to the WLAN AP.

13. The wireless communication device of claim 8, wherein the request to operate in the SMPS mode comprises an SMPS request in accordance with an 802.11n wireless communication protocol.

14. The wireless communication device of claim 8, wherein the one or more processors are configured to execute computer-executable instructions stored within the memory to further cause the wireless communication device to:

retransmit the message indicating the request to operate in the SMPS mode up to a maximum repeat request number of times; and

maintain, in the operational state, the wireless circuitry configured to use the MIMO mode that includes at least two spatial streams for communication between the wireless communication device and the WLAN AP when receiving at least one packet from the WLAN AP that uses at least two spatial streams after a corresponding guard interval following each retransmitted message.

15. A non-transitory computer-readable medium storing instructions for configuring wireless circuitry of a wireless communication device, the instructions, when executed by one or more processors, cause the wireless communication device to:

transmit a message indicating a request to operate in a spatial multiplexing power save (SMPS) mode to a wireless local area network (WLAN) access point (AP) associated with the wireless communication device, the SMPS mode supporting only one spatial stream in a single-input single-output (SISO) mode;

monitor packets received from the WLAN AP after transmitting the message and following a guard interval;

maintain, in an operational state, the wireless circuitry configured to use a multiple-input multiple-output (MIMO) mode that includes at least two spatial streams for communication between the wireless communication device and the WLAN AP, when receiving at least one packet from the WLAN AP that uses at least two spatial streams; and

configure the wireless circuitry to use the SISO mode, which includes only a single spatial stream for communication between the wireless communication device and the WLAN AP, when all packets received from the WLAN AP after the guard interval use only one spatial stream, and the number of packets received equals or exceeds a minimum successive packet threshold.

16. The non-transitory computer-readable medium of claim 15, wherein the minimum successive packet threshold comprises at least one hundred successive packets received after the guard interval, and wherein the guard interval spans at least one hundred milliseconds.

17. The non-transitory computer-readable medium of claim 15, wherein the wireless communication device configures the wireless circuitry to use the MIMO mode by enabling at least two least two radio frequency (RF) receive chains to process the at least two spatial streams.

18. The non-transitory computer-readable medium of claim 15, wherein the wireless communication device configures the wireless circuitry to use the SISO mode by enabling only one radio frequency (RF) receive chain to process the single spatial stream received from the WLAN AP.

19. The non-transitory computer-readable medium of claim 15, wherein the request to operate in the SMPS mode comprises an SMPS request in accordance with an 802.11n wireless communication protocol.

20. The non-transitory computer-readable medium of claim 15, wherein execution of the instructions by the one or more processors, further cause the wireless communication device to:

retransmit the message indicating the request to operate in the SMPS mode up to a maximum repeat request number of times; and

maintain, in the operational state, the wireless circuitry configured to use the MIMO mode that includes at least two spatial streams for communication between the wireless communication device and the WLAN AP when receiving at least one packet from the WLAN AP that uses at least two spatial streams after a corresponding guard interval following each retransmitted message.