Sounding Schemes Using Distributed Tones In Wireless Communications

Abstract

Various examples pertaining to sounding schemes using distributed tones in wireless communications are described. A stations (STA) receives a sounding signal with an extremely-high-throughput (EHT) null data packet (NDP). The STA then transmits a feedback regarding the sounding signal on a distributed-tone resource unit (DT-RU).

What is claimed is: 
     
         1 . A method, comprising:
 receiving a sounding signal with an extremely-high-throughput (EHT) null data packet (NDP); and   transmitting a feedback regarding the sounding signal on a distributed-tone resource unit (DT-RU).   
     
     
         2 . The method of  claim 1 , wherein the EHT NDP contains a legacy preamble, a Universal Signal field (U-SIG) and an EHT Signal field (EHT-SIG) duplicated for each of four 20 MHz sub-channels of a 80 MHz frequency segment. 
     
     
         3 . The method of  claim 2 , wherein the receiving of the sounding signal comprises performing 80 MHz packet detection and maximum ratio combining (MRC) over the four 20 MHz sub-channels on the U-SIG and the EHT-SIG. 
     
     
         4 . The method of  claim 2 , wherein the U-SIG indicates a physical-layer protocol data unit (PPDU) format as either EHT or EHT distributed-tone (EHT DT). 
     
     
         5 . The method of  claim 2 , wherein the EHT NDP further contains a distributed-tone short training field (DT-STF) and a distributed-tone long training field (DT-LTF) for the 80 MHz frequency segment. 
     
     
         6 . The method of  claim 5 , wherein each of the DT-STF and the DT-LTF contains respective one or more DT-RUs for one or more target stations (STAs) of the sounding signal with each of the respective one or more DT-RUs corresponding to a respective one of the one or more target STAs. 
     
     
         7 . The method of  claim 5 , wherein each of the DT-STF and the DT-LTF contains a predetermined set of distributed tones for each bandwidth, and wherein each distributed tone in the predetermined set of distributed tones has non-zero energy while other tones are null tones with zero energy. 
     
     
         8 . The method of  claim 7 , wherein the transmitting of the feedback comprises transmitting a compressed beamforming feedback on one or more distributed tones in the predetermined set of distributed tones. 
     
     
         9 . The method of  claim 7 , wherein distributed tones in the predetermined set of distributed tones do not match with one or more DT-RUs corresponding to one or more target stations (STAs) of the sounding signal. 
     
     
         10 . The method of  claim 7 , wherein every two adjacent distributed tones in the respective predetermined set of distributed tones are separated by N−1 tones, 2≤N≤13. 
     
     
         11 . The method of  claim 1 , wherein the EHT NDP comprises a mixed-format NDP that contains continuous tones and predetermined distributed tones on different frequency segments. 
     
     
         12 . The method of  claim 11 , wherein the different frequency segments comprises at least a first 80 MHz frequency segment a second 80 MHz frequency segment, wherein the first 80 MHz frequency segment uses a first EHT long training field (EHT-LTF) with the continuous tones, and wherein the second 80 MHz frequency segment uses a second EHT-LTF with the distributed tones. 
     
     
         13 . The method of  claim 1 , further comprising:
 determining a type of the EHT NDP based on an EHT NDP Announcement frame or based on a Universal Signal field (U-SIG) in the EHT NDP; and   receiving a feedback trigger which triggers the transmitting of the feedback.   
     
     
         14 . The method of  claim 13 , wherein, responsive to determining the type of the EHT NDP based on the EHT NDP Announcement frame, a first frequency segment or a first RU using continuous tones and a second frequency segment or a second RU using distributed tones are indicated by the EHT NDP Announcement frame. 
     
     
         15 . A method, comprising:
 transmitting a sounding signal with an extremely-high-throughput (EHT) null data packet (NDP); and   receiving a feedback regarding the sounding signal on a distributed-tone resource unit (DT-RU).   
     
     
         16 . The method of  claim 15 , wherein the EHT NDP contains a legacy preamble, a Universal Signal field (U-SIG) and an EHT Signal field (EHT-SIG) duplicated for each of four 20 MHz sub-channels of a 80 MHz frequency segment, wherein the U-SIG indicates a physical-layer protocol data unit (PPDU) format as either EHT or EHT distributed-tone (EHT DT), wherein the EHT NDP further contains a distributed-tone short training field (DT-STF) and a distributed-tone long training field (DT-LTF) for the 80 MHz frequency segment. 
     
     
         17 . The method of  claim 16 , wherein each of the DT-STF and the DT-LTF contains either:
 respective one or more DT-RUs for one or more target stations (STAs) of the sounding signal with each of the respective one or more DT-RUs corresponding to a respective one of the one or more target STAs; or   a predetermined set of distributed tones for each bandwidth with each distributed tone in the predetermined set of distributed tones having non-zero energy and with other tones having zero energy,   wherein distributed tones in the predetermined set of distributed tones do not match with one or more DT-RUs corresponding to the one or more target STAs of the sounding signal, and   wherein every two adjacent distributed tones in the respective predetermined set of distributed tones are separated by N−1 tones, 2≤N≤13.   
     
     
         18 . The method of  claim 15 , wherein the EHT NDP comprises a mixed-format NDP that contains continuous tones and predetermined distributed tones on different frequency segments, wherein the different frequency segments comprises at least a first 80 MHz frequency segment a second 80 MHz frequency segment, wherein the first 80 MHz frequency segment uses a first EHT long training field (EHT-LTF) with the continuous tones, and wherein the second 80 MHz frequency segment uses a second EHT-LTF with the distributed tones. 
     
     
         19 . The method of  claim 15 , further comprising:
 transmitting an EHT NDP Announcement frame that indicates a type of the EHT NDP; and   transmitting a feedback trigger which causes the receiving of the feedback,   wherein a first frequency segment or a first RU using continuous tones and a second frequency segment or a second RU using distributed tones are indicated by the EHT NDP Announcement frame.   
     
     
         20 . An apparatus, comprising:
 a transceiver configured to communicate wirelessly; and   a processor coupled to the transceiver and configured to perform operations comprising:
 receiving, via the transceiver, a sounding signal with an extremely-high-throughput (EHT) null data packet (NDP); and 
 transmitting, via the transceiver, a feedback regarding the sounding signal on a distributed-tone resource unit (DT-RU), 
   wherein:
 the EHT NDP contains a legacy preamble, a Universal Signal field (U-SIG) and an EHT Signal field (EHT-SIG) duplicated for each of four 20 MHz sub-channels of a 80 MHz frequency segment, 
 the receiving of the sounding signal comprises performing 80 MHz packet detection and maximum ratio combining (MRC) over the four 20 MHz sub-channels on the U-SIG and the EHT-SIG, 
 the U-SIG indicates a physical-layer protocol data unit (PPDU) format as either EHT or EHT distributed-tone (EHT DT), and 
 the EHT NDP further contains a distributed-tone short training field (DT-STF) and a distributed-tone long training field (DT-LTF) for the 80 MHz frequency segment.