TRANSMISSION OPPORTUNITY OPERATION OF UPLINK MULTI-USER MULTIPLE-INPUT-MULTIPLE-OUTPUT COMMUNICATION IN WIRELESS NETWORKS

• US 20140269544A1
• Filed: 09/10/2013
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Zhu, Chunhui, Kim, Youngsoo
• Granted Patent: US 9,419,752 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint

Abstract

Wireless communication in a wireless network comprises a wireless station obtaining a transmission opportunity period (TXOP) for communicating with an access point (AP) over a wireless communication channel. The wireless station sends an announcement to the AP to share the transmission opportunity period with at least another wireless station, as a multi-user transmission opportunity period for simultaneously transmitting data from said wireless stations to the AP on multiple uplink (UL) spatial streams over the wireless channel. UL TXOP transmission information is communicated based on one or more indications included in a quality of service (QoS) data frame and a frame header.

Claims

1. A method of wireless communication, comprising:

a wireless station obtaining a transmission opportunity (TXOP) period for communicating with an access point (AP) over a wireless communication channel;

the wireless station sending an announcement to the AP to share the TXOP period with at least another wireless station, as a multi-user TXOP period for simultaneously transmitting data from said wireless stations to the AP on multiple uplink (UL) spatial streams over the wireless channel; and

communicating UL transmission information in one or more indications included in a quality of service (QoS) data frame and a frame header.

2. The method of claim 1, wherein the wireless stations use the QoS data frame for delivering UL traffic and a QoS control field of the QoS data frame for indicating one or more of station buffer size and time required for clearing the station buffer.

3. The method of claim 2, wherein the stations use one of a TXOP Duration Requested sub-field or a Queue Size sub field in the QoS control field for indications of one or more of station buffer size and time required for clearing the station buffer for informing the AP to determine which stations to poll for UL transmissions.

4. The method of claim 3, further comprising:

uplink data transmission in a wireless network comprising a wireless local area network (WLAN), wherein the data frames are organized into access categories in order of transmission priority;

contending for channel access by performing Enhanced Distributed Channel Access (EDCA) to provide QoS for a data frame in a high priority access category;

the AP performing downlink transmission of an acknowledgment to each wireless station in response to one or more uplink data frames,

wherein the transmitting said announcement comprises transmitting an uplink transmission request (UTR), wherein the uplink data transmission comprises uplink multi-user multiple-input-multiple-output (UL MU-MIMO) communication from target wireless stations to the AP.

5. The method of claim 4, further comprising:

using a More Data sub-field in a frame-control field of the frame header to inform the AP whether more data frames are to be transmitted in the UL transmission during a next TXOP period, wherein the frame header comprises a media access control (MAC) header.

6. The method of claim 5, wherein transmitting a UTR comprises transmitting a UTR control frame, the UTR control from comprising:

a Duration/ID field indicating a requested TXOP duration and any control overhead;

a receiver address (RA) field including the MAC address of the AP;

a Transmitter Address (TA) field including the MAC address of the wireless station owner of the TXOP; and

an Access Category (AC) field in the frame body indicating the AC that obtains a TXOP.

7. The method of claim 6, wherein communicating UL TXOP transmission information comprises indicating early termination of a TXOP period in a last received QoS data frame that a TXOP period owner transmits based on one or more of:

setting the More Data sub-field to 0,

setting the TXOP Duration Requested sub-field in a QoS control field to 0, and

setting the Duration/ID field to cover only a response frame.

8. The method of claim 7, wherein communicating UL TXOP transmission information further comprises:

requesting an extension of a TXOP period transmission by the TXOP period owner if required to complete a transmission by indicating to the AP by the TXOP period owner intent to extend a current TXOP period based on one or more of;

setting the More Data sub-field to 1,

setting the TXOP Duration Requested sub-field in the QoS control field to a new requested duration, and

setting the Duration/ID field to cover duration required to empty an AC queue.

9. The method of claim 8, further comprising:

the AP transmits an uplink transmission indication (UTI) frame to all target wireless stations along with addresses of target wireless stations allowed to transmit in the AP in the uplink phase, and the allowed uplink transmission time for each target wireless station.

10. The method of claim 9, wherein a UTI frame and a CF-Multi-Poll frame comprises a TXOP period limit, and a UL MU-MIMO TXOP is protected by a network allocation vector (NAV) set by the Duration field of the UTI frame or the CF-Multi-Poll+Ack frame.

11. The method of claim 10, wherein NAV operation during a TXOP period comprises:

a UTR frame setting the NAVs of all stations that receive the UTR frame;

a UTI frame updating the NAVs of all stations except those stations being polled by the UTI frame, whose NAVs are reset to allow UL transmission;

a CF-Multi-Poll+Ack frame updating the NAVs of all stations except those being polled by the UTI frame, whose NAVs Are reset to allow UL transmission; and

a station resetting its NAV upon receiving a CF-End or CF-End+CF-Ack frame.

12. The method of claim 11, wherein:

upon a station receiving a UTI frame or a CF-Multi-Poll+Ack frame containing a basic service set identifier (BSSID) of a basic service set (BSS) in which the station is associated, that station updates the NAV if necessary.

13. A wireless station, comprising:

a Physical Layer (PHY) for wireless communication over a wireless communication channel;

Media Access Control (MAC) layer; and

a channel access module that obtains a transmission opportunity period (TXOP) for communicating with an access point (AP) over a wireless communication channel, wherein the channel access module sends an announcement to the AP to share the transmission opportunity period with at least another wireless station as a multi-user transmission opportunity period for simultaneously transmitting data from said wireless stations to the AP on multiple uplink (UL) spatial streams over the wireless channel, and communicates transmission information in one or more indications included in a quality of service (QoS) data frame and a frame header.

14. The wireless station of claim 13, wherein the wireless stations use the QoS data frame for delivering UL traffic and a QoS control field of the QoS data frame for indicating one or more of station buffer size and time required for clearing the station buffer.

15. The wireless station of claim 14, wherein the stations use one of a TXOP Duration Requested sub-field or a Queue Size sub field in the QoS control field for indications of one or more of station buffer size and time required for clearing the station buffer for informing the AP to determine which stations to poll for UL transmissions.

16. The wireless station of claim 15, wherein the channel access module provides uplink data transmission in a wireless local area network (WLAN), wherein the data frames are organized into access categories in order of transmission priority, contends for channel access by performing Enhanced Distributed Channel Access (EDCA) to provide QoS for a data frame in a high priority access category;

wherein the AP performs downlink transmission of an acknowledgment to each wireless station in response to one or more uplink data frames,

wherein the announcement comprises an uplink transmission request (UTR),

wherein the uplink data transmission comprises uplink multi-user multiple-input-multiple-output (UL MU-MIMO) communication from target wireless stations to the AP.

17. The wireless station of claim 16, wherein the channel access module uses a More Data sub-field in a frame-control field of the frame header to inform the AP whether more data frames are to be transmitted in the UL transmission during a next TXOP period, wherein the frame header comprises a MAC header.

18. The wireless station of claim 17, wherein the channel access module indicates early termination of a TXOP period in a last received QoS data frame that a TXOP period owner transmits based on one or more of:

setting the More Data sub-field to 0,

setting the TXOP Duration Requested sub-field in a QoS control field to 0, and

setting a Duration/ID field to cover only a response frame.

19. The wireless station of claim 18, wherein an extension of a TXOP period transmission is requested by the TXOP period owner if required to complete a transmission by indicating to the AP by the TXOP period owner intent to extend a current TXOP period based on the channel access module performing one or more of:

setting the More Data sub-field to 1,

setting the TXOP Duration Requested sub-field in the QoS control field to a new requested duration, and

setting the Duration/ID field to cover duration required to empty an AC queue.

20. The wireless station of claim 19, wherein the channel access module provides network allocation vector (NAV) operations during a TXOP period, wherein the channel access module uses:

a UTR frame to set the NAVs of all stations that receive the UTR frame, an uplink transmission indication (UTI) frame to update the NAVs of all stations except those stations being polled by the UTI frame, whose NAVs are reset to allow UL transmission, a CF-Multi-Poll+Ack frame to update the NAVs of all stations except those being polled by the UTI frame, whose NAVs Are reset to allow UL transmission, and a station to reset its NAV upon receiving a CF-End or CF-End+CF-Ack frame.

21. The wireless station of claim 20, wherein:

upon a station receiving a UTI frame or a CF-Multi-Poll+Ack frame containing a basic service set identifier (BSSID) of a basic service set (BSS) in which the station is associated, that station updates the NAV if necessary.

22. A wireless access point, comprising:

a Physical Layer (PHY) for wireless communication over a wireless communication channel; and

Media Access Control (MAC) layer that manages simultaneous transmissions from multiple wireless stations to the access point on multiple uplink (UL) spatial streams during a multi-user transmission opportunity period over a wireless channel,

wherein the access point (AP) receives transmission information in on one or more indications included in a quality of service (QoS) data frame and a frame header.

23. The wireless access point of claim 22, wherein the wireless stations use the QoS data frame for delivering UL traffic and a QoS control field of the QoS data frame to the AP for indicating one or more of station buffer size and time required for clearing the station buffer.

24. The wireless access point of claim 23, wherein the stations use one of a TXOP Duration Requested sub-field or a Queue Size sub field in the QoS control field for indications of one or more of station buffer size and time required for clearing the station buffer for informing the AP to determine which stations to poll for UL transmissions.

25. The wireless access point of claim 24, wherein the AP comprises a channel access module that provides uplink data transmission in a wireless local area network (WLAN), wherein the data frames are organized into access categories in order of transmission priority, contends for channel access by performing Enhanced Distributed Channel Access (EDCA) to provide QoS for a data frame in a high priority access category;

wherein the AP performs downlink transmission of an acknowledgment to each wireless station in response to one or more uplink data frames,

wherein the announcement comprises an uplink transmission request (UTR),

wherein the uplink data transmission comprises uplink multi-user multiple-input-multiple-output (UL MU-MIMO) communication from target wireless stations to the AP.

26. The wireless access point of claim 25, wherein the channel access module uses a More Data sub-field in a frame-control field of the frame header to inform the AP whether more data frames are to be transmitted in the UL transmission during a next TXOP period, wherein the frame header comprises a MAC header.

27. The wireless access point of claim 26, wherein the channel access module indicates early termination of a TXOP period in a last received QoS data frame that a TXOP period owner transmits based on one or more of:

setting the More Data sub-field to 0,

setting the TXOP Duration Requested sub-field in a QoS control field to 0, and

setting a Duration/ID field to cover only a response frame.

28. The wireless Access point of claim 27, wherein an extension of a TXOP period transmission is requested by the TXOP period owner if required to complete a transmission by indicating to the AP by the TXOP owner intent to extend a current TXOP period based on the channel access module performing one or more of:

setting the More Data sub-field to 1,

setting the TXOP Duration Requested sub-field in the QoS control field to a new requested duration, and

setting the Duration/ID field to cover duration required to empty an AC queue.

29. The wireless access point of claim 28, wherein the channel access module provides network allocation vector (NAV) operations during a TXOP period, wherein the channel access module uses:

a UTR frame to set the NAVs of all stations that receive the UTR frame, an uplink transmission indication (UTI) frame to update the NAVs of all stations except those stations being polled by the UTI frame, whose NAVs are reset to allow UL transmission, a CF-Multi-Poll+Ack frame to update the NAVs of all stations except those being polled by the UTI frame, whose NAVs Are reset to allow UL transmission, and a station to reset its NAV upon receiving a CF-End or CF-End+CF-Ack frame.

30. The wireless access point of claim 29, wherein:

upon a station receiving a UTI frame or a CF-Multi-Poll+Ack frame containing a basic service set identifier (BSSID) of a basic service set (BSS) in which the station is associated, that station updates the NAV if necessary.