Data transmission method and apparatus in wireless local area network

Patent metadata

Field	Value
Publication number	US-10686640-B2
Application number	US-201815987216-A
Country	US
Kind code	B2
Filing date	May 23, 2018
Priority date	Nov 23, 2015
Publication date	Jun 16, 2020
Grant date	Jun 16, 2020

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 channel estimation information transmission method, comprising:
determining, by an apparatus, a high efficiency long training field (HE-LTF) sequence in frequency domain according to a transmission bandwidth and a mode of a HE-LTF field;
sending, by the apparatus, a time-domain signal, according to the determined HE-LTF sequence and a number of orthogonal frequency division multiplexing (OFDM) symbols of the HE-LTF field (N HELTF );
wherein the HE-LTF sequence in the frequency domain in a 1× HE-LTF mode over a 160 MHz bandwidth corresponds to:
HE-LTF=[P1×LTF 80MHz_Primary ,BI, P 2×LTF 80MHz_Secondary ], wherein P 1 is +1 , P 2 is +1 or 1,

LTF 80MHz_Primary ={L -LTF 80MHz_A , 0 , R -LTF 80MHz_A },
LTF 80MHz_Secondary ={L -LTF 80MHz_A , 0, −1 ×R -LTF 80MHz_A }

and the BI is a sequence carried on a subcarrier between subcarriers on edges of two 80 MHz channels;

wherein {L-LTF 80MHz_A , 0, R-LTF 80MHz_A }=HE-LTF 250 (−500:4:500), and

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Assignees

• Huawei Tech Co Ltd

Inventors

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

Classifications

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04L25/02 Primary

  Details {; arrangements for supplying electrical power along data transmission lines (systems for transmitting signals via power distribution lines H04B3/54)} · CPC title

• H04W84/12

  WLAN [Wireless Local Area Networks] · CPC title

• H04L27/2695

  with channel estimation, e.g. determination of delay spread, derivative or peak tracking (channel estimation H04L25/0202) · CPC title

• H04L27/26

  Systems using multi-frequency codes (H04L27/32 takes precedence) · CPC title