Compressed Feedback Format for WLAN

An apparatus, comprising:

• a network interface device associated with a first communication device, the network interface device implemented on one or more integrated circuits, wherein the network interface device comprises:
• a media access control (MAC) processor implemented on the one or more integrated circuits;
• and
• a physical layer (PHY) processor implemented on the one or more integrated circuits;
• wherein the one or more integrated circuits are configured to:
• perform multiuser (MU) transmissions and single user (SU) transmissions,
• control the network interface device to transmit a sounding packet modulated using orthogonal frequency division multiplexing (OFDM),
• process a feedback packet that was transmitted by a second communication device and received by the first communication device, the feedback packet including a feedback report corresponding to the sounding packet, and
• use information from the feedback report to control the network interface device to beamform a transmission to the second communication device;
• wherein when the feedback packet is in connection with an MU transmission, the feedback report includes:
• i) a plurality of angle values associated with one or more OFDM tones corresponding to the sounding packet,
• ii) deltas corresponding to per-tone signal to noise ratios (PT-SNRs) associated with at least some of the one or more OFDM tones corresponding to the first sounding packet, wherein each delta corresponds to a difference between the respective PT-SNR and an average signal to noise ratio (avg-SNR) from a set of one of one or more avg-SNRs, and
• iii) the set of one or more avg-SNRs, wherein the set of one or more avg-SNRs are associated with a set of one or more spatial or space-time streams;
• wherein when the feedback packet is in connection with an SU transmission, the feedback report does not include any deltas corresponding to PT-SNRs associated with the sounding packet.

A method, comprising:

• receiving, at a first communication device, a sounding packet modulated using orthogonal frequency division multiplexing (OFDM);
• determining, at the first communication device, whether the sounding packet is for a multiuser (MU) transmission or a single user (SU) transmission;
• generating, at the first communication device, a feedback packet that includes a feedback report corresponding to the sounding packet, wherein the feedback report provides information to facilitate the second communication device beamforming a transmission to the first communication device;
• and
• transmitting, with the first communication device, the feedback packet to the second communication device;
• wherein when the first communication device determines that the sounding packet is for an MU transmission, the feedback report includes:
• i) a plurality of angle values associated with one or more OFDM tones corresponding to the first sounding packet,
• ii) deltas corresponding to per-tone signal to noise ratios (PT-SNRs) associated with at least some of the one or more OFDM tones corresponding to the first sounding packet, wherein each delta corresponds to a difference between the respective PT-SNR and an average signal to noise ratio (avg-SNR) from a set of one of one or more avg-SNRs, and
• iii) the set of one or more avg-SNRs, wherein the set of one or more avg-SNRs are associated with a set of one or more spatial or space-time streams;
• wherein when the first communication device determines that the sounding packet is for an SU transmission, the feedback report does not include any deltas corresponding to PT-SNRs associated with the sounding packet.

An apparatus, comprising:

• a network interface device associated with a first communication device, the network interface device implemented on one or more integrated circuits, wherein the network interface device comprises:
• a media access control (MAC) processor implemented on the one or more integrated circuits;
• and
• a physical layer (PHY) processor implemented on the one or more integrated circuits;
• wherein the one or more integrated circuits are configured to:
• process a sounding packet modulated using orthogonal frequency division multiplexing (OFDM), the sounding packet transmitted by a second communication device and received by the first communication device,
• determine whether the sounding packet is for a multiuser (MU) transmission or a single user (SU) transmission,
• generate a feedback packet that includes a feedback report corresponding to the sounding packet, wherein the feedback report provides information to facilitate the second communication device beamforming a transmission to the first communication device, and
• control the network interface device to the feedback packet to the second communication device;
• wherein the one or more integrated circuits are configured to, when the one or more integrated circuits determine that the sounding packet is for an MU transmission, generate the feedback report to include:
• i) a plurality of angle values associated with one or more OFDM tones corresponding to the first sounding packet,
• ii) deltas corresponding to per-tone signal to noise ratios (PT-SNRs) associated with at least some of the one or more OFDM tones corresponding to the first sounding packet, wherein each delta corresponds to a difference between the respective PT-SNR and an average signal to noise ratio (avg-SNR) from a set of one of one or more avg-SNRs, and
• iii) the set of one or more avg-SNRs, wherein the set of one or more avg-SNRs are associated with a set of one or more spatial or space-time streams;
• wherein the one or more integrated circuits are configured to, when the one or more integrated circuits determine that the sounding packet is for an SU transmission, generate the feedback report to not include any deltas corresponding to PT-SNRs associated with the sounding packet.