Master station and method for high-efficiency Wi-Fi (HEW) communication using a multiple access technique
Embodiments of a master station and method for communicating with a plurality of high-efficiency Wi-Fi (HEW) devices in a wireless network are generally described herein. In some embodiments, the master station may contend for a wireless medium during a contention period to receive control of the medium for an HEW control period, and transmit an HEW control and schedule transmission at the beginning of the HEW control period. The HEW control and schedule transmission may include a schedule indicating channel resources for communications with the HEW devices during the HEW control period in accordance with a non-contention based multiple access technique. The channel resources indicated in the HEW control and schedule transmission may comprise subspaces within a wideband legacy channel bandwidth. Transmissions on HEW channels during the HEW control period may have symbol times aligned within each legacy channel for legacy-device coexistence.
1. An apparatus arranged to communicate with a plurality of high-efficiency (HE) devices, the apparatus comprising:
memory and processing circuitry configured to:
generate a control frame to be transmitted to a plurality of stations (STAs), the control frame to trigger a response within a transmission opportunity (TXOP), the control frame to identify stations (STAs) for transmission of uplink multi-user data units within the TXOP and to allocate resources for transmission of the uplink multi-user data units, within the TXOP, by each of the identified STAs; and
process,
in accordance with one of a multi-user multiple-input multiple-output (MU-MIMO) or an orthogonal frequency division multiple access (OFDMA) technique, within the TXOP one or more of the uplink multi-user data units from at least some of the identified STAs.
2. The apparatus of claim 1 wherein the control frame is a downlink multi-user frame and comprises a high-efficient (HE) signal field (HE-SIG) to allocate resource units to each of the identified STAs.
3. The apparatus of claim 2 wherein the HE-SIG is configurable for transmission on one or more of a plurality of 20 MHz subbands of a 40 MHz subchannel, an 80 MHz channel, or a 160 MHz subchannel.
4. The apparatus of claim 2 wherein the allocated resources comprise resource unit assignments of less than 20 MHz for uplink OFDMA transmissions within one or more of a 20 MHz bandwidth, a 40 MHz bandwidth, an 80 MHz bandwidth, and a 160 MHz bandwidth.
5. The apparatus of claim 3 wherein the control frame comprises:
a legacy preamble duplicated on each of the 20 MHz subbands, the legacy preamble comprising one or more legacy training fields and a legacy signal field; and
a HE long training field (HE-LTF) that is orthogonal for different space-time streams.
6. The apparatus of claim 1 wherein the apparatus is further configured to obtain the TXOP prior to transmission of the control frame, wherein the control frame is configured to be transmitted within the current TXOP, and
wherein the one or more uplink multi-user data units are received within the TXOP from the STAs on the allocated resources in response to the control frame.
7. The apparatus of claim 6 wherein the apparatus is configured to contend for a wireless medium during a contention period to receive control of the medium for a control period, the control period being within the TXOP.
8. The apparatus of claim 6 wherein the apparatus is configured to receive the uplink multi-user data units within a time-frequency space arranged for OFDMA communications within the TXOP.
9. The apparatus of claim 4 wherein the resource unit assignments of less than 2.0 MHz for uplink OFDMA transmissions comprise HE channel bandwidths one or more of 10 MHz, 5 MHz, 2.5 MHz, and 1 MHz sub-portions of a 20 MHz bandwidth.
10. The apparatus of claim 2 wherein the control frame is configured to trigger a frame exchange within the TXOP, the control frame and response being part of the frame exchange, and
wherein the control frame is configurable to identify STAs for receipt of downlink multi-user data units within the TXOP.
11. The apparatus of claim 2 wherein the control frame is a downlink multi-user (MU) media-access control (MAC) protocol data unit (DL MU MPDU), and
wherein the uplink multi-user data units received from at least some of the identified STAs comprise uplink (UL) MU MPDUs (UL MU MPDUs).
12. The apparatus of claim 11 wherein the control frame is a trigger frame that allocates resources for random access transmission of the UL MU MPDUs within the TXOP by each of the identified STAs.
13. The apparatus of claim 1 wherein the apparatus is configured to be part of an access point, and
wherein the apparatus further comprises e transceiver circuitry to transmit the control frame within the TXOP and to receive the uplink multi-user data units within the TXOP.
14. The apparatus of claim 13 further comprising two or more antennas coupled to the transceiver circuitry.
15. Anon-transitory computer-readable storage medium that stores instructions for execution by one or more processors to perform operations to:
generate a control frame to be transmitted to a plurality of stations (STAs), the control frame to trigger a response within a transmission opportunity (TXOP), the control frame to identify stations (STAs) for transmission of uplink multi-user data units within the TXOP and to allocate resources for transmission of the uplink multi-user data units, within the TXOP, by each of the identified STAs; and
process,
in accordance with one of a multi-user multiple-input multiple-output (MU-MIMO) or an orthogonal frequency division multiple access (OFDMA) technique, within the TXOP, one or more of the uplink multi-user data units from at least some of the identified STAs.
16. The non-transitory computer-readable storage medium of claim 15 wherein the control frame is a downlink multi-user frame and comprises a high-efficient (RE) signal field (HE-SIG) to allocate resource units to each of the identified STAs.
17. The non-transitory computer-readable storage medium of claim 16 wherein the HE-SIG is configurable for transmission on one or more of a plurality of 20 MHz subbands of a 40 MHz subchannel, an 80 MHz channel, or a 160 MHz subchannel.
18. The non-transitory computer-readable storage medium of claim 16 wherein the allocated resources comprise resource unit assignments of less than 20 MHz for uplink OFDMA transmissions within one or more of a 20 MHz bandwidth, a 40 MHz bandwidth, an 80 MHz bandwidth, and a 160 MHz bandwidth.
19. A method performed by one or more processors, the method comprising:
generating a control frame to be transmitted to a plurality of stations (STAs), the control frame to trigger a response within a transmission opportunity (TXOP), the control frame to identify stations (STAs) for transmission of uplink multi-user data units within the TXOP and to allocate resources for transmission of the uplink multi-user data units, within the TXOP, by each of the identified STAs; and
processing,
in accordance with one of a multi-user multiple-input multiple-output (MU-MIMO) or an orthogonal frequency division multiple access (OFDMA) technique, within the TXOP one or more of the uplink multi-user data units from at least some of the identified STAs.
20. The method of claim 19 wherein the control frame is a downlink multi-user frame and comprises a high-efficient (RE) signal field (HE-SIG) to allocate resource units to each of the identified STAs,
wherein the HE-SIG is configurable for transmission on one or more of a plurality of 20 MHz subbands of a 40 MHz subchannel, an 80 MHz channel, or a 160 MHz subchannel, and
wherein the control frame comprises:
a legacy preamble duplicated on each of the 20 MHz subbands, the legacy preamble comprising one or more legacy training fields and a legacy signal field; and
a HE long training field (HE-LTF) that is orthogonal for different space-time streams.