Data transmission method and apparatus in wireless local area network

Patent metadata

Field	Value
Publication number	US-12244447-B2
Application number	US-202318309575-A
Country	US
Kind code	B2
Filing date	Apr 28, 2023
Priority date	Nov 23, 2015
Publication date	Mar 4, 2025
Grant date	Mar 4, 2025

Abstract

An HE-LTF transmission method is provided, including: determining, based on a total number N STS of space-time streams, a number N HELTF of OFDM symbols included in an HE-LTF field; determining a HE-LTF sequence in frequency domain according to a transmission bandwidth and a mode of the HE-LTF field, where the HE-LTF sequence in frequency domain includes but is not limited to a mode of the HE-LTF field sequence that is in a 1× mode and that is mentioned in implementations; and sending a time-domain signal according to the number N HELTF of OFDM symbols and the determined HE-LTF sequence in frequency domain. In the foregoing solution, a PAPR value is relatively low.

First claim

What is claimed is:

1. A method for channel estimation information transmission, the method comprising:
determining, by an apparatus, a long training field (LTF) sequence in a frequency domain according to a transmission bandwidth (BW) and a mode of a LTF field; and
sending, by the apparatus, a time-domain signal according to the LTF sequence in the frequency domain and a number of orthogonal frequency division multiplexing (OFDM) symbols of the LTF field;
wherein the LTF sequence in the frequency domain in a 1× LTF mode over a bandwidth that includes multiple 80 MHz channels that comprises any combination of the following: a left part of a long training field sequence of a 80 MHz channel (L-LTF 80MHz_A ), a right part of the long training field sequence of the 80 MHz channel (R-LTF 80MHz_A ), −L-LTF 80MHz_A , or −R-LTF 800MHZ_A ;
wherein the L-LTF 800MHz_A comprises {−1, −1, +1, +1, +1, +1, +1, −1, −1, −1, +1, +1, −1, −1, +1, −1, +1, −1, −1, −1, −1, −1, −1, +1, +1, −1, −1, +1, −1, +1, −1, −1, −1, −1, −1, +1, +1, −1, −1, +1, −1, +1, −1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, −1, −1, −1, −1, +1, −1, −1, −1, −1, −1, −1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, −1, +1, +1, −1, −1, +1, −1, +1, −1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, −1, −1, −1, −1, +1, −1, +1, −1, −1} on subcarriers with every fourth index; and
wherein the R-LTF 80MHZ_A comprises {−1, +1, +1, −1, −1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, −1, −1, −1, −1, −1, +1, +1, −1, −1, +1, −1, +1, −1, +1, +1, +1, +1, −1, +1, −1, −1, +1, −1, −1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, −1, +1, +1, −1, −1, +1, −1, +1, −1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, −1, −1, −1, −1, +1, −1, +1, −1, −1, −1, +1, +1} on subcarriers with every fourth index.

2. The method according to claim 1 ,
wherein the bandwidth includes a first 80 MHz channel and a second 80 MHz channel following the first 80 MHz channel in the frequency domain;
wherein the LTF sequence in the frequency domain includes a sequence BI, and the sequence BI is a sequence carried on a subcarrier between subcarriers of edge of the first 80 MHz channel and subcarrier of edge of the right second 80 MHz channel; and
wherein the sequence BI is full 0.

3. The method according to claim 1 , further comprising:
before determining the LTF sequence in the frequency domain, receiving a trigger frame to indicate uplink scheduling information in an uplink multi-user multiple-input multiple-output (UL-MU-MIMO) transmission, wherein the uplink scheduling information includes the transmission BW and the number of OFDM symbols of the LTF field.

4. The method according to claim 1 , further comprising:
determining the number of OFDM symbols of the LTF field based on a total number of space-time streams (N STS ) in a single user transmission or in a downlink multi-user multiple-input multiple-output (DL-MU-MIMO) transmission, wherein the number of OFDM symbols of the LTF field and the N STS correspond as follows:

number of OFDM symbols of

N STS
the LTF field

1
1

2
2

3
4

4
4

5
6

6
6

7
8

8
 8.

5. The method according to claim 1 , wherein the L-LTF 80MHz_A further comprises 0 on remaining subcarriers, and the R-LTF 80MHz_A further comprises 0 on remaining subcarriers.

6. The method according to claim 2 , wherein the LTF sequence in the frequency domain is HE-LTF 500 (−1012:4:1012), HE-LTF 500 (−1012:4:1012)={L-LTF 80M_A , 0, R-LTF 80M_A , BI, L-LTF 80M_A , 0, −1*R-LTF 80M_A }.

7. The method according to claim 2 , wherein the LTF sequence in the frequency domain is HE-LTF 500 (−1012:4:1012), HE-LTF 500 (−1012:4:1012)={L-LTF 80M_A , 0, R-LTF 80M_A , BI, −1*L-LTF 80M_A , 0, R-LTF 80M_A }.

8. A method for channel estimation information processing, the method comprising:
receiving, by an apparatus, a preamble that comprises a long training field (LTF); and
obtaining, by the apparatus, a channel estimation value of a corresponding subcarrier location according to the received LTF and a LTF sequence in a frequency domain;
wherein the LTF sequence in the frequency domain in a 1× LTF mode over a bandwidth that includes multiple 80 MHz channels comprises any combination of the following: a left part of a long training field sequence of a 80 MHz channel (L-LTF 80MHZ_A ), a right part of the long training field sequence of the 80 MHz channel (R-LTF 80MHZ_A ), −L-LTF 80MHZ_A , or −R-LTF 80MHZ_A ;
wherein the L-LTF 80MHZ_A comprises {−1, −1, +1, +1, +1, +1, +1, −1, −1, −1, +1, +1, −1, −1, +1, −1, +1, −1, −1, −1, −1, −1, −1, +1, +1, −1, −1, +1, −1, +1, −1, −1, −1, −1, −1, +1, +1, −1, −1, +1, −1, +1, −1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, −1, −1, −1, −1, +1, −1, −1, −1, −1, −1, −1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, −1, +1, +1, −1, −1, +1, −1, +1, −1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, −1, −1, −1, −1, +1, −1, +1, −1, −1} on subcarriers with every fourth index; and
wherein the R-LTF 80MHZ_A comprises {−1, +1, +1, −1, −1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, −1, −1, −1, −1, −1, +1, +1, −1, −1, +1, −1, +1, −1, +1, +1, +1, +1, −1, +1, −1, −1, +1, −1, −1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, +1, +1, +1, −1, +1, +1, −1, −1, +1, −1, +1, −1, +1, +1, +1, +1, +1, −1, −1, +1, +1, −1, +1, −1, +1, −1, −1, −1, −1, +1, −1, +1, −1, −1, −1, +1, +1} on subcarriers with every fourth index.

9. The method according to claim 8 ,
wherein the bandwidth includes a first 80 MHz channel and a second 80 MHz channel following the first 80 MHz channel in the frequency domain;
wherein the LTF sequence in the frequency domain includes a sequence BI, and the sequence BI is a sequence carried on a subcarrier between subcarriers of edges of the first 80 MHz channel and subcarrier of edge of the second 80 MHz channel; and
wherein the sequence BI is full 0.

10. The method according to claim 8 , further comprising:
before receiving the preamble that

Assignees

• Huawei Tech Co Ltd

Inventors

• Lin Wei
• Xue Xin
• Wang Ningjuan
• Liu Le

Classifications

• H04W72/1268

  of uplink data flows · CPC title

• H04W24/10

  Scheduling measurement reports {; Arrangements for measurement reports} · CPC title

• H04L27/2601

  Multicarrier modulation systems · CPC title

• H04L25/022

  of frequency response · CPC title

• H04B7/0452

  Multi-user MIMO systems · CPC title