LTF design for WLAN system

Patent metadata

Field	Value
Publication number	US-2016119047-A1
Application number	US-201514756914-A
Country	US
Kind code	A1
Filing date	Oct 28, 2015
Priority date	Oct 28, 2014
Publication date	Apr 28, 2016
Grant date	—

Abstract

In an example of wireless multi-user communication, a station may generate a frame and provide the frame for transmission to multiple stations. The frame may include a long training field (LTF) portion and a data portion. The LTF portion and the data portion may be associated with a plurality of tones. Each group of the plurality of tones in the data portion may be associated with a respective steering matrix. Each group of the plurality of tones in the data portion may include two or more tones of the plurality of tones. One or more of the multiple stations may receive the frame and process the frame. Other methods, apparatus, and computer-readable media are also disclosed.

First claim

What is claimed is:

1 . A method for a transmitting apparatus to transmit a frame, the method comprising:
generating a frame, the frame comprising a long training field (LTF) portion and a data portion which are associated with a plurality of tones, wherein each group of the plurality of tones in the data portion is associated with a respective steering matrix, and each group of the plurality of tones in the data portion comprises two or more tones of the plurality of tones; and providing the frame for transmission.

2 . The method of claim 1 , wherein a training sequence is allocated to every other tone of the plurality of tones in the LTF portion for a spatial stream.

3 . The method of claim 1 , wherein the LTF portion is a compressed LTF portion.

4 . The method of claim 1 , wherein the two or more tones of the plurality of tones in the data portion comprise consecutive tones.

5 . The method of claim 1 , wherein the two or more tones of the plurality of tones in the data portion comprise an integer multiple of two tones.

6 . The method of claim 1 , wherein each group of the plurality of tones in the data portion is associated with a respective cyclic shift value.

7 . The method of claim 1 , wherein the LTF portion comprises a first frequency region allocated for a first station and a second frequency region allocated for a second station.

8 . The method of claim 7 , wherein a number of space-time streams (STSs) associated with the first station is different from a number of STSs associated with the second station.

9 . The method of claim 1 , wherein an Orthogonal Frequency Division Multiplexing (OFDM) symbol of the LTF portion has a duration of 6.4 μs excluding any cyclic prefix (CP) duration.

10 . The method of claim 1 , wherein the frame further comprises an omni-directional portion.

11 . The method of claim 10 , wherein the omni-directional portion comprises legacy header fields, a repeated legacy signal (R-L-SIG) field, and one or more high efficiency signal (HE-SIG) fields.

12 . The method of claim 1 , wherein the frame comprises a beamformed portion, wherein the beamformed portion comprises a high efficiency short training field (HE-STF), an HE-LTF, and an HE data field, and wherein the HE-LTF is the LTF portion.

13 . The method of claim 1 , wherein tones in the LTF portion, except every other tone of the plurality of tones in the LTF portion, are null tones.

14 . A method for a receiving apparatus to receive a frame, the method comprising:
receiving a frame, the frame comprising a long training field (LTF) portion and a data portion which are associated with a plurality of tones, wherein each group of the plurality of tones in the data portion is associated with a respective steering matrix, and each group of the plurality of tones in the data portion comprises two or more tones of the plurality of tones; processing the LTF portion; and processing the data portion.

15 . The method of claim 14 , wherein a training sequence is allocated to every other tone of the plurality of tones in the LTF portion for a spatial stream.

16 . The method of claim 14 , wherein the LTF portion is a compressed LTF portion.

17 . The method of claim 14 , wherein the two or more tones of the plurality of tones in the data portion comprise consecutive tones.

18 . The method of claim 14 , wherein the two or more tones of the plurality of tones in the data portion comprise an integer multiple of two tones.

19 . The method of claim 14 , wherein each group of the plurality of tones in the data portion is associated with a respective cyclic shift value.

20 . The method of claim 14 , wherein processing the LTF portion comprises estimating a channel based on the LTF portion, and processing the data portion comprises decoding data based on the estimated channel.

Assignees

• Newracom Inc

Inventors

• Lee Daewon

Classifications

• H04W84/12

  WLAN [Wireless Local Area Networks] · CPC title

• H04L27/2613

  Structure of the reference signals · CPC title

• H04L5/0048

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title

• H04W28/06

  Optimizing {the usage of the radio link}, e.g. header compression, information sizing {, discarding information (system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365)} · CPC title

• H04B7/0617 Primary

  for beam forming · CPC title