Acknowledgement for multiple user communication in a WLAN

An apparatus, comprising:

• a network interface device having one or more integrated circuit devices configured to
• generate independent data for multiple communication devices to be included in a single multi-user (MU) physical layer (PHY) data unit,
• generate respective control frames corresponding to at least some of the second communication devices, wherein the respective control frames are configured to prompt the at least some of the second communication devices to transmit an orthogonal frequency division multiple access (OFDMA) PHY data unit to acknowledge that the at least some of the second communication devices received the MU PHY data unit, and wherein the respective control frames are for inclusion in the single MU PHY data unit,
• transmit the single MU PHY data unit to the multiple communication devices, the single MU PHY data unit including the independent data for the multiple second communication devices and the respective control frames corresponding to the at least some of the second communication devices,
• receive the OFDMA PHY data unit from the at least some of the communication devices, the OFDMA PHY data unit corresponding to an acknowledgment of the single MU PHY data unit by the at least some of the communication devices, and
• process the OFDMA PHY data unit to determine that the at least some of the multiple communication devices received the single MU PHY data unit.

A method for acknowledging a multi-user (MU) physical layer (PHY) data unit, the method comprising:

• receiving, at a first communication device, the MU PHY data unit, the MU PHY data unit having:
• i) independent data for the first communication device and one or more second communication devices, the MU PHY data unit having been transmitted by a third communication device, wherein data corresponding to the first communication device is in included in the MU PHY data unit in a first frequency subband within a communication channel spanned by the MU PHY data unit, and
• ii) control frames corresponding to the first communication device and at least some of the one or more second communication devices, wherein the control frames are configured to prompt the first communication device and the at least some of the one or more second communication devices to transmit an orthogonal frequency division multiple access (OFDMA) PHY data unit to acknowledge that the at least some of the second communication devices received the MU PHY data unit;
• determining, at the first communication device, a second frequency subband in which the first communication device is to transmit as part of the OFDMA PHY data unit, the OFDMA PHY data unit for acknowledging, by the first communication device and the at least some of the one or more second communication devices, the MU PHY data unit;
• generating, at the first communication device, a portion of the OFDMA PHY data unit so that the portion of the OFDMA PHY data unit corresponds to the second frequency subband;
• and
• transmitting, at the first communication device, the portion of the OFDMA PHY data unit while the at least some of the one or more second communication devices transmit one or more other portions of the OFDMA PHY data unit to acknowledge the MU PHY data unit.

An apparatus, comprising:

• a network interface device having one or more integrate circuits configured to
• receive a multi-user (MU) physical layer (PHY) data unit, the MU PHY data unit having:
• i) independent data for a first communication device and one or more second communication devices, the MU PHY data unit having been transmitted by a third communication device, wherein data corresponding to the first communication device is in included in the MU PHY data unit in a first frequency subband within a communication channel spanned by the MU PHY data unit, and
• ii) control frames corresponding to the first communication device and at least some of the one or more second communication devices, wherein the control frames are configured to prompt the first communication device and the at least some of the one or more second communication devices to transmit an orthogonal frequency division multiple access (OFDMA) PHY data unit to acknowledge that the at least some of the second communication devices received the MU PHY data unit,
• determine a second frequency subband in which the first communication device is to transmit as part of the OFDMA PHY data unit, the OFDMA PHY data unit for acknowledging, by the first communication device and the at least some of the one or more second communication devices, the MU PHY data unit,
• generate a portion of the OFDMA PHY data unit so that the portion of the OFDMA PHY data unit corresponds to the second frequency subband, and
• transmit the portion of the OFDMA PHY data unit while the one or more second communication devices transmit one or more other portions of the OFDMA PHY data unit to acknowledge the MU PHY data unit.