Trigger frame design for short feedback
Methods and apparatus are described by which a wireless station transmits information to an access point in response to a short feedback request. The response to the short feedback request is transmitted as either energy or lack thereof in one or more long training fields transmitted in a preamble of a physical layer packet. Short feedback trigger frames for requesting the short feedback are also described.
1. An apparatus for a wireless access point (AP), the apparatus comprising:
memory and processing circuitry, wherein the processing circuitry is to:
encode a medium access control (MAC) layer short feedback trigger frame to request a short feedback response from one or more stations (STAs) wherein the short feedback trigger frame includes a feedback type field that indicates a type of feedback that is to be elicited from the one or more STAs; and,
decode short feedback responses from the one or more STAs where the short feedback response from a particular STA is encoded as energy or lack thereof in one or more high-efficiency long training fields (HE-LTFs) of a physical layer packet in a particular resource block (RB) identified by a resource block identification (RBID) assigned to the particular STA that defines a particular resource unit (RU) and particular spatial stream (SS).
2. The apparatus of claim 1 wherein the feedback type field indicates a type of feedback selected from a group that includes a resource request, a power save (PS) poll, or a location service measurement request.
3. The apparatus of claim 1 wherein the short feedback trigger frame includes an indication in a trigger type field that short feedback is requested.
4. The apparatus of claim 1 wherein the short feedback trigger frame includes a group identification (groupID) field that indicates which of the one or more STAs are to respond to the short feedback request.
5. The apparatus of claim 4 wherein the groupID field includes a value that allows STAs with a previously assigned RBID to respond or a value that allows STAs belonging to a particular group to respond, wherein the group is identified by an RBID set that includes particular RBID values.
6. The apparatus of claim 1 wherein the short feedback trigger frame includes one or more per-RBIDs_set info fields that each contain information to define a set of RBIDs and information as to whether the set of RBIDs are to be used for STAs with assigned RBIDs or can be randomly selected by a STA without a pre-assigned RBID.
7. The apparatus of claim 6 wherein the per-RBIDs_set info fields includes a min RBID field and a max RBID field to define the set of RBIDs as being all RBIDs between the minimum and maximum RBID values contained in the min and max RBID fields.
8. The apparatus of claim 1 wherein the short feedback trigger frame includes an indication of the number of bits to be transmitted in the short feedback response as a corresponding number of LTFs.
9. The apparatus of claim 1 wherein the short feedback trigger frame includes a rotation value by which a STA calculates an effective RBID as a function of its previously assigned RBID.
10. The apparatus of claim 1 wherein the processing circuitry is to demodulate HE-LTFs in multi-user null data packets (MU-NDPs) transmitted by STAs responding to the short feedback request.
11. An apparatus for a wireless station (STA), the apparatus comprising:
memory and processing circuitry, wherein the processing circuitry is to:
decode a medium access control (MAC) layer short feedback trigger frame from an access point (AP) that requests a short feedback response, wherein the short feedback response is to be encoded as energy or lack thereof in one or more high-efficiency long training fields (HE-LTFs) of a physical layer packet in a particular resource block (RB) identified by a resource block identification (RBID) assigned to the STA that defines a particular resource unit (RU) and particular spatial stream (SS); and,
encode the short feedback response in a multi-user null data packet (MU NDP).
12. The apparatus of claim 11 wherein the short feedback trigger frame includes a feedback type field that indicates a type of feedback that is to be transmitted.
13. The apparatus of claim 12 wherein the feedback type field indicates a feedback type selected from a group that includes a resource request, a power save (PS) poll, or a location service measurement request.
14. The apparatus of claim 11 wherein the short feedback trigger frame includes an indication in a trigger type field that indicates short feedback is requested.
15. The apparatus of claim 11 wherein the short feedback trigger frame includes a group identification (groupID) field that indicates which STAs are to respond to the short feedback request.
16. The apparatus of claim 15 wherein the groupID field includes a value that allows STAs with a previously assigned RBID to respond or a value that allows STAs belonging to a particular group to respond, wherein the group is identified by an RBID set containing particular RBID values.
17. The apparatus of claim 11 wherein the short feedback trigger frame includes one or more per-RBIDs_set info fields that each include information to define a set of RBIDs and information as to whether the set of RBIDs are to be used for STAs with assigned RBIDs or can be randomly selected by a STA without a pre-assigned RBID.
18. The apparatus of claim 17 wherein the per-RBIDs_set info fields contains a min RBID field and a max RBID field to define the set of RBIDs as being all RBIDs between the minimum and maximum RBID values contained in the min and max RBID fields.
19. The apparatus of claim 11 wherein the short feedback trigger frame includes an indication of the number of bits to be transmitted in the short feedback response as a corresponding number of LTFs.
20. The apparatus of claim 11 wherein the short feedback trigger frame contains a rotation value by which the STA calculates an effective RBID as a function of a previously assigned RBID.
21. A non-transitory computer-readable medium comprising instructions to cause a wireless access point (AP), upon execution of the instructions by processing circuitry of the AP, to:
encode a medium access control (MAC) layer short feedback trigger frame to request a short feedback response from one or more stations (STAs) wherein the short feedback trigger frame includes a feedback type field that indicates a type of feedback that is to be elicited from the one or more STAs; and,
decode short feedback responses from the one or more STAs where the short feedback response from a particular STA is encoded as energy or lack thereof in one or more high-efficiency long training fields (HE-LTFs) of a physical layer packet in a particular resource block (RB) identified by a resource block identification (RBID) assigned to the particular STA that defines a particular resource unit (RU) and particular spatial stream (SS).
22. The non-transitory medium of claim 21 wherein the feedback type field indicates a feedback type selected from a group that includes a resource request, a power save (PS) poll, or a location service measurement request.
23. The non-transitory medium of claim 21 wherein the short feedback trigger frame includes an indication in a trigger type field that indicates short feedback is requested.
24. The non-transitory medium of claim 21 wherein the short feedback trigger frame includes a group identification (groupID) field that indicates which STAs are to respond to the short feedback request.
25. The non-transitory medium of claim 24 wherein the groupID field includes a value that allows STAs with a previously assigned RBID to respond or a value that allows STAs belonging to a particular group to respond, wherein the group is identified by an RBID set containing particular RBID values.