Enhanced channel sounding reports for WLAN systems
Methods and apparatuses for channel sounding reports may be used in wireless local area network (WLAN) systems. A station (STA) may receive, from an access point (AP), a beacon frame. The STA may receive, from the AP, a null data packet (NDP) announcement (NDPA) frame including an indication of subchannels for measuring channel characteristics. The STA may receive, from the AP, an NDP frame. The STA may transmit, to the AP, a feedback report frame including channel state information (CSI) feedback, wherein the CSI feedback is based on measurements that the STA performed on the received NDP frame using the indicated subchannels for measuring channel characteristics. The beacon frame may include indications of punctured subchannel(s) and subchannel(s) that is not punctured, which may be indicated as a disabled subchannel bitmap. The subchannels for measuring channel characteristics may be equal to or a subset of the subchannel(s) that is not punctured.
1 . A station (STA) configured to perform a sounding procedure, the STA comprising:
a processor; and
a transceiver, wherein
the processor and the transceiver are configured to:
receive, from an access point (AP), a beacon frame, wherein the beacon frame includes a first indication of at least one punctured subchannel;
receive, from the AP, a null data packet (NDP) announcement (NDPA) frame including a second indication of the at least one punctured subchannel and an indication of at least one subchannel for measuring channel characteristics, wherein the at least one subchannel for measuring channel characteristics include at least one non-punctured subchannel other than the indicated at least one punctured subchannel;
receive, from the AP, an NDP frame; and
transmit, to the AP, a feedback report frame, on subchannels excluding the at least one punctured subchannel, including a universal signal (U-SIG) field indicating the at least one punctured subchannel and channel state information (CSI) feedback, wherein the CSI feedback is based on measurements that the STA performed on the received NDP frame using the indicated subchannels for measuring channel characteristics.
2 . The STA of claim 1 , wherein the indication of the at least one punctured subchannel is indicated as a disabled subchannel bitmap.
3 . The STA of claim 1 , wherein the subchannels for measuring channel characteristics do not include the indicated at least one punctured subchannel.
4 . The STA of claim 1 , wherein the indication of the at least one punctured subchannel is included in an extremely high throughput (EHT) operation element of the received beacon frame.
5 . The STA of claim 1 , wherein the subchannels for measuring channel characteristics are 20 MHz channels.
6 . The STA of claim 1 , wherein the feedback report frame is included in a multi-user (MU) physical layer protocol data unit (PPDU).
7 . The STA of claim 1 , wherein the feedback report frame further includes channel quality information (CQI), wherein the CQI is based on the measurements that the STA performed on the received NDP frame using the indicated subchannels for measuring channel characteristics.
8 . The STA of claim 1 , wherein the feedback report frame is transmitted on at least one of the indicated subchannels for measuring channel characteristics.
9 . The STA of claim 1 , wherein the processor and the transceiver are further configured to:
receive, from the AP, a trigger frame including an indication of subchannels for transmitting the CSI feedback, wherein the feedback report frame is transmitted in response to the received trigger frame and on the indicated subchannels for transmitting the CSI feedback.
10 . The STA of claim 1 , wherein the CSI feedback includes an index of a quantized beamforming matrix V.
11 . A method for sounding performed by a station (STA), the method comprising:
receiving, from an access point (AP), a beacon frame, wherein the beacon frame includes a first indication of at least one punctured subchannel;
receiving, from the AP, a null data packet (NDP) announcement (NDPA) frame including a second indication of the at least one punctured subchannel and an indication of at least one subchannel for measuring channel characteristics, wherein the at least one subchannel for measuring channel characteristics include at least one non-punctured subchannel other than the indicated at least one punctured subchannel;
receiving, from the AP, an NDP frame; and
transmitting, to the AP, a feedback report frame, on subchannels excluding the at least one punctured subchannel, including a universal signal (U-SIG) field indicating the at least one punctured subchannel and channel state information (CSI) feedback, wherein the CSI feedback is based on measurements that the STA performed on the received NDP frame using the indicated subchannels for measuring channel characteristics.
12 . The method of claim 11 , wherein the indication of the at least one punctured subchannel is indicated as a disabled subchannel bitmap.
13 . The method of claim 11 , wherein the subchannels for measuring channel characteristics do not include the indicated at least one punctured subchannel.
14 . The method of claim 11 , wherein the indication of the at least one punctured subchannel is included in an extremely high throughput (EHT) operation element of the received beacon frame.
15 . The method of claim 11 , wherein the subchannels for measuring channel characteristics are 20 MHz channels.
16 . The method of claim 11 , wherein the feedback report frame is included in a multi-user (MU) physical layer protocol data unit (PPDU).
17 . The method of claim 11 , wherein the feedback report frame further includes channel quality information (CQI), wherein the CQI is based on the measurements that the STA performed on the received NDP frame using the indicated subchannels for measuring channel characteristics.
18 . The method of claim 11 , wherein the feedback report frame is transmitted on at least one of the indicated subchannels for measuring channel characteristics.
19 . The method of claim 11 , further comprising:
receiving, from the AP, a trigger frame including an indication of subchannels for transmitting the CSI feedback, wherein the feedback report frame is transmitted in response to the received trigger frame and on the indicated subchannels for transmitting the CSI feedback.
20 . The method of claim 11 , wherein the CSI feedback includes an index of a quantized beamforming matrix V.