Generating and processing multi-user data units for WLAN

Patent metadata

Field	Value
Publication number	US-10693533-B2
Application number	US-201615063218-A
Country	US
Kind code	B2
Filing date	Mar 7, 2016
Priority date	Oct 23, 2009
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

A first field of a preamble includes a plurality of indications of respective numbers of spatial or space-time streams for respective receivers to enable each receiver among the multiple receivers to determine a respective set of one or more training sequences, in a plurality of training sequences, that corresponds to the receiver. A second field of the preamble includes respective modulation and coding scheme information for the respective receivers. The preamble is generated such that i) the first field is transmitted prior to the plurality of training sequences, and ii) the second field of the preamble is transmitted after the plurality of training sequences are transmitted. A data portion of the multi-user data unit is generated using respective modulation and coding schemes for the respective receivers. The multi-user data unit is transmitted such that data for the respective receivers are transmitted via respective sets of one or more spatial or space-time streams.

First claim

What is claimed is:

1. A method for generating a multi-user data unit for transmission via a multiple input, multiple output (MIMO) communication channel, the method comprising:
generating, at a communication device, a multi-user data unit having a preamble and a data portion, wherein the preamble of the multi-user data unit includes a plurality of training sequences, a first field, and a second field, wherein the preamble of the multi-user data unit is structured such that i) the first field of the preamble precedes the plurality of training sequences, and ii) the plurality of training sequences precedes the second field of the preamble, wherein the plurality of training sequences are to be used by multiple receivers for channel estimation, wherein the first field of the preamble includes a plurality of indications of respective numbers of spatial or space-time streams for respective receivers of the multiple receivers to enable each respective receiver of the multiple receivers to determine a respective set of one or more training sequences, in the plurality of training sequences, that corresponds to the respective receiver, wherein the second field of the preamble includes respective modulation and coding scheme information for the respective receivers of the multiple receivers, and wherein the data portion of the multi-user data unit is to be transmitted using respective modulation and coding schemes for the respective receivers of the multiple receivers; and
transmitting, with the communication device, the multi-user data unit.

2. The method of claim 1 , wherein the plurality of indications of respective numbers of spatial or space-time streams are ordered according to an order.

3. The method of claim 2 , further comprising:
generating, at the communication device, another data unit that includes information indicating the order, wherein the other data unit is to be transmitted prior to the first field of the preamble.

4. The method of claim 1 , wherein transmitting the multi-user data unit comprises:
transmitting, with the communication device, the first field of the preamble in an omni-directional mode; and
respectively beam-steering, with the communication device, the second field of the preamble to the respective receivers of the multiple receivers.

5. The method of claim 4 , wherein transmitting the multi-user data unit further comprises:
respectively beam-steering, with the communication device, respective sets of one or more training sequences to the respective receivers of the multiple receivers.

6. The method of claim 1 , wherein a first sub-field of the first field of the preamble includes a first indicator of a first set of one or more training sequences that corresponds to a first receiver of the multiple receivers;
wherein a second sub-field of the first field of the preamble includes a second indicator of a second set of one or more training sequences that corresponds to a second receiver of the multiple receivers.

7. An apparatus, comprising:
a wireless network interface device having one or more integrated circuits, wherein the wireless network interface device is configured to:
generate a multi-user data unit having a preamble and a data portion, wherein the preamble of the multi-user data unit includes a plurality of training sequences, a first field, and a second field, wherein the preamble of the multi-user data unit is structured such that i) the first field of the preamble precedes the plurality of training sequences, and ii) the plurality of training sequences precedes the second field of the preamble, wherein the plurality of training sequences are to be used by multiple receivers for channel estimation, wherein the first field of the preamble includes a plurality of indications of respective numbers of spatial or space-time streams for respective receivers of the multiple receivers to enable each respective receiver of the multiple receivers to determine a respective set of one or more training sequences, in the plurality of training sequences, that corresponds to the respective receiver, wherein the second field of the preamble includes respective modulation and coding scheme information for the respective receivers of the multiple receivers, and wherein the data portion of the multi-user data unit is to be transmitted using respective modulation and coding schemes for the respective receivers of the multiple receivers; and
transmit the multi-user data unit.

8. The apparatus of claim 7 , wherein the plurality of indications of respective numbers of spatial or space-time streams are ordered according to an order.

9. The apparatus of claim 8 , wherein the wireless network interface device is further configured to:
generate another data unit that includes information indicating the order, wherein the other data unit is to be transmitted prior to the first field of the preamble.

10. The apparatus of claim 7 , wherein the wireless network interface device is further configured to:
transmit the first field of the preamble in an omni-directional mode; and
respectively beam-steer the second field of the preamble to the respective receivers of the multiple receivers.

11. The apparatus of claim 10 , wherein the wireless network interface device is further configured to respectively beam-steer respective sets of one or more training sequences to the respective receivers of the multiple receivers.

12. The apparatus of claim 7 , wherein a first sub-field of the first field of the preamble includes a first indicator of a first set of one or more training sequences that corresponds to a first receiver of the multiple receivers;
wherein a second sub-field of the first field of the preamble includes a second indicator of a second set of one or more training sequences that corresponds to a second receiver of the multiple receivers.

13. A method for processing a multi-user data unit received via a multiple input, multiple output (MIMO) communication channel, the method comprising:
receiving, at a communication device, a multi-user data unit having a preamble and a data portion, wherein the preamble of the multi-user data unit includes a plurality of training sequences, a first field, and a second field, wherein the preamble of the multi-user data unit is structured such that i) the first field of the preamble precedes the plurality of training sequences, and ii) the plurality of training sequences precedes the second field of the preamble, wherein the plurality of training sequences corresponds to multiple receivers, wherein the communication device is one of the multiple receivers, wherein the first field of the preamble includes a plurality of indications of respective numbers of spatial or space-time streams for respective receivers of the multiple receivers to enable each respective receiver of the multiple receivers to determine a respective set of one or more training sequences, in the plurality of training sequences, that corresponds to the respective receiver, and wherein the second field of the preamble includes respective modulation and coding scheme information for the respective receivers of the multiple receivers;
processing, at the communication device, the first field of the preamble to determine a respective set of one or more training sequences which corresponds to the communication device;
generating, at the communication device, a channel estimate during the determined set of one or more training sequences which corresponds to the communication device;
using the channel estimate to process, at the communication device, the second field of the preamble; and
using, at the communication device, a modulation and codin

Assignees

• Huawei Tech Co Ltd

Inventors

• Zhang Hongyuan
• Banerjea Raja
• Liu Yong
• Yu Mao

Classifications

• H04B7/0669 Primary

  using different channel coding between antennas (space-time coding H04L1/0618) · CPC title

• H04L5/0053

  Allocation of signalling, i.e. of overhead other than pilot signals · CPC title

• H04L5/0023

  Time-frequency-space · CPC title

• H04L1/0618

  Space-time coding · CPC title

• H04L5/005

  of common pilots, i.e. pilots destined for multiple users or terminals · CPC title