Training sequence indication for WLAN

Patent metadata

Field	Value
Publication number	US-9281877-B2
Application number	US-201414269976-A
Country	US
Kind code	B2
Filing date	May 5, 2014
Priority date	Oct 23, 2009
Publication date	Mar 8, 2016
Grant date	Mar 8, 2016

Abstract

In a method for generating a preamble of a data unit for transmission via a multiple input, multiple output (MIMO) communication channel, a first field of the preamble is generated. The first field provides a plurality of indicators to a plurality of receivers. Each one of the plurality of indicators indicates a set of a plurality of training sequences that corresponds to transmission of the data unit to a corresponding one of the plurality of receivers. The plurality of training sequences is included in a second field of the preamble. The preamble is formatted such that the first field of the preamble will be transmitted prior to the second field of the preamble being transmitted.

First claim

What is claimed is:

1. A method for generating a data unit for transmission via a multiple input, multiple output (MIMO) communication channel, the method comprising:
generating, at a communication device, a plurality of training sequences to be included in a preamble of the data unit;
when the data unit is to be transmitted in a single user mode in which the data unit is intended for a single receiver,
generating, at the communication device, a first field of the preamble to include an indicator that the data unit is being transmitted in the single user mode, and
generating, at the communication device, a second field of the preamble to include bits of an identifier of the single receiver;

when the data unit is being transmitted in a multi-user mode in which the data unit is intended for multiple receivers,
generating, at the communication device, the first field of the preamble to include an indicator that the data unit is being transmitted in the multi-user mode, and
generating, at the communication device, the second field of the preamble to include one or more indications of one or more sets of training signals in the preamble, the one or more sets of training signals corresponding to transmission of the data unit to one or more receivers;

generating, at the communication device, the preamble such that the first field of the preamble and the second field of the preamble will be transmitted prior to the plurality of training sequences being transmitted; and
generating, at the communication device, the data unit to include the preamble such that,
when the data unit is transmitted in the single user mode, the preamble includes i) the indicator that the data unit is being transmitted in the single user mode in the first field, and ii) bits of the identifier of the single receiver in the second field, and
when the data unit is transmitted in the multi-user mode, the preamble includes i) the indicator that the data unit is being transmitted in the multi-user mode in the first field, and ii) the one or more indications of one or more sets of training signals in the second field.

2. The method of claim 1 , further comprising:
when the data unit is to be transmitted in the single user mode,
generating, at the communication device, a third field of the preamble to include modulation and coding scheme information for the data unit; and

when the data unit is being transmitted in the multi-user mode,
generating, at the communication device, a fourth field of the preamble to include modulation and coding scheme information for the data unit, wherein the fourth field is separate from the third field.

3. The method of claim 1 , further comprising:
when the data unit is to be transmitted in the single user mode,
generating, at the communication device, a third field of the preamble to include an indication of a number of spatial or space time streams; and

when the data unit is being transmitted in the multi-user mode,
generating, at the communication device, the third field of the preamble to include an indication of a number of spatial or space time streams corresponding to a first receiver among the multiple receivers.

4. The method of claim 3 , wherein:
when the data unit is being transmitted in the multi-user mode, the one or more indications of one or more sets of training signals in the preamble comprise one or more indications of one or more numbers of spatial or space time streams corresponding to one or more second receivers among the multiple receivers.

5. The method of claim 1 , wherein generating the second field of the preamble to include bits of the identifier of the single receiver comprises generating the second field of the preamble to include only a subset of bits of the identifier of the single receiver.

6. The method of claim 1 , wherein generating the second field of the preamble to include bits of the identifier of the single receiver comprises generating the second field of the preamble to include bits of an association identifier (AID) of the single receiver.

7. An apparatus, comprising:
a physical layer (PHY) processing device having one or more integrated circuits configured to:
generate a plurality of training sequences to be included in a preamble of a data unit to be transmitted via a multiple input, multiple output (MIMO) communication channel,
when the data unit is to be transmitted in a single user mode in which the data unit is intended for a single receiver,
generate a first field of the preamble to include an indicator that the data unit is being transmitted in the single user mode, and
generate a second field of the preamble to include bits of an identifier of the single receiver,

when the data unit is being transmitted in a multi-user mode in which the data unit is intended for multiple receivers,
generate the first field of the preamble to include an indicator that the data unit is being transmitted in the multi-user mode, and
generate the second field of the preamble to include one or more indications of one or more sets of training signals in the preamble, the one or more sets of training signals corresponding to transmission of the data unit to one or more receivers;

wherein the one or more integrated circuits are further configured to:
generate the preamble such that the first field of the preamble and the second field of the preamble will be transmitted prior to the plurality of training sequences being transmitted, and
generate the data unit to include the preamble such that,
when the data unit is transmitted in the single user mode, the preamble includes i) the indicator that the data unit is being transmitted in the single user mode in the first field, and ii) bits of the identifier of the single receiver in the second field, and
when the data unit is transmitted in the multi-user mode, the preamble includes i) the indicator that the data unit is being transmitted in the multi-user mode in the first field, and ii) the one or more indications of one or more sets of training signals in the second field.

8. The apparatus of claim 7 , wherein the one or more integrated circuits are further configured to:
when the data unit is to be transmitted in the single user mode,
generate a third field of the preamble to include modulation and coding scheme information for the data unit, and
when the data unit is being transmitted in the multi-user mode,
generate a fourth field of the preamble to include modulation and coding scheme information for the data unit, wherein the fourth field is separate from the third field.

9. The apparatus of claim 7 , wherein the one or more integrated circuits are further configured to:
when the data unit is to be transmitted in the single user mode,
generate a third field of the preamble to include an indication of a number of spatial or space time streams, and
when the data unit is being transmitted in the multi-user mode,
generate the third field of the preamble to include an indication of a number of spatial or space time streams corresponding to a first receiver among the multiple receivers.

10. The apparatus of claim 9 , wherein:
when the data unit is being transmitted in the multi-user mode, the one or more indications of one or more sets of training signals in the preamble comprise one or more indications of one or more numbers of spatial or space time streams corresponding to one or more second receivers among the multiple receivers.

11. The apparatus of claim 7 , wherein the one or more integrated circuits are configured to generate the second field of the preamble to include only a subset of bits of the identifier of the single receiver when the data unit is to be tr

Assignees

• Marvell World Trade 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

• H04L25/0226

  sounding signals per se · CPC title

• H04B7/0413 Primary

  MIMO systems · CPC title

• H04L5/0023

  Time-frequency-space · CPC title

• H04L5/0048 Primary

  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