Coexistent channel access method

• US 8,830,973 B2
• Filed: 11/24/2009
• Issued: 09/09/2014
• Est. Priority Date: 02/18/2009
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Seok, Yong Ho
• Primary Examiner(s): Lai, Andrew
• Assistant Examiner(s): HENSON, JAMAAL R
• Application Number:
  US13/202,028
• Publication Number:
  US 20110305233A1
• Time in Patent Office: 1,750 Days
• Field of Search: 455/41.2, 455/355, 370/338, 370/329
• US Class Current: 370/338
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0665 Feed forward of transmit weights to the receiver
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 52/248 where transmission power control commands are generated based on a path parameter
• CPC Class Codes: H04W 52/281 taking into account user or data type priority
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 52/52 using AGC [Automatic Gain Control] circuits or amplifiers
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/0473 the resource being transmission power
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

According to an embodiment of present invention, a method for transmitting a coexistent data stream, the method including: transmitting coexistent data stream transmission information including transmission power information of a first data stream targeted for a first station and transmission power information of a second data stream targeted for a second station in an environment in which the first station, a legacy station, coexists with a second station, a station supporting a wireless local area network (WLAN) system evolved further than the first station; and transmitting, by an access point (AP), the first and second data streams to the second station and the first station, wherein the AP transmits the first data stream with a higher transmission power level than that of the second data stream according to the coexistent data stream transmission information.

Claims

1. A method of transmitting a multiple input multiple output (MIMO) packet in a wireless local area network, the method comprising:

generating a short training field (STF) used for at least one receiver to estimate an automatic gain control and a coarse frequency offset;

generating a long training field (LTF) used for the at least one receiver to estimate a fine frequency offset;

generating a Very High Throughput (VHT)-signal field;

generating a VHT-STF used for improving automatic gain control estimation in a MIMO transmission;

generating a VHT-LTF used for estimating a MIMO channel based on a plurality of data streams;

generating a first signal field including a length field indicating a length of the plurality of data streams;

generating a data frame sequentially including the STF, the LTF, the VHT-signal field, the VHT-STF, the VHT-LTF, the first signal field and the plurality of data streams; and

transmitting the data frame to the at least one receiver,

wherein the first signal field is subsequent to the VHT-LTF and precedes the plurality of data streams, and

wherein the VHT-signal field includes first information, second information and third information, the first information indicating that the plurality of data streams in the data frame are simultaneously received by the at least one receiver, the second information indicating which receiver is targeted for the plurality of data streams, and the third information indicating a bandwidth used for a transmission of the plurality of data streams.

2. The method of claim 1, wherein the data frame is a physical layer convergence procedure (PLCP) protocol data unit (PPDU).

3. The method of claim 1, wherein the bandwidth is one of 20 MHz, 40 MHz and 80 MHz.

4. A wireless device of transmitting a multiple input multiple output (MIMO) packet in a wireless local area network, comprising:

a processor; and

a memory operatively coupled with the processor and storing instructions that when executed by the processor causes to the device to;

generate a short training field (STF) used for at least one receiver to estimate an automatic gain control and a coarse frequency offset;

generate a long training field (LTF) used for the at least one receiver to estimate a fine frequency offset;

generate a Very High Throughput (VHT)-signal field;

generate a VHT-STF used for improving automatic gain control estimation in a MIMO transmission;

generate a VHT-LTF used for estimating a MIMO channel;

generate a first signal field including a length field indicating a length of a plurality of data streams;

generate a data frame sequentially including the STF, the LTF, the VHT-signal field, the VHT-STF, the VHT-LTF, the first signal field and the plurality of data streams; and

transmit the data frame to the at least one receiver,

wherein the first signal field is subsequent to the VHT-LTF, and

wherein the VHT-signal field includes first information, second information and third information, the first information indicating that the plurality of data streams in the data frame are simultaneously received by the at least one receiver, the second information indicating which receiver is targeted for the plurality of data streams, and the third information indicating a bandwidth for the plurality of data streams.

5. The wireless device of claim 4, wherein the data frame is a physical layer convergence procedure (PLCP) protocol data unit (PPDU).

6. The wireless device of claim 4, wherein the bandwidth is one of 20 MHz, 40 MHz and 80 MHz.