METHOD, APPARATUS, AND COMPUTER READABLE MEDIUM FOR TRANSMITTING PILOTS IN WIRELESS LOCAL AREA NETWORKS

1 . A wireless communication station (STA), the STA comprising circuitry configured to:

receive one or more packets, indicating a pilot pattern for the wireless communications STA to use;

transmit a first pilot carrier in a lower subcarrier of a frequency allocation according to the pilot pattern; and

transmit a second pilot carrier in a higher subcarrier of the frequency allocation according to the pilot pattern.

2 . The wireless communication STA of claim 1 , wherein the one or more packets further indicate a schedule for the wireless communications device to transmit in a transmit opportunity (TXOP), and wherein the circuitry is configured to transmit in the TXOP.

3 . The wireless communication STA of claim 2 , wherein the circuitry is further configured to transmit and receive in accordance with Orthogonal Frequency Division Multiple Access (OFDMA).

4 . The wireless communication STA of any of claim 1 , wherein the circuitry is configured to transmit the first pilot carrier and the second pilot carrier simultaneously.

5 . The wireless communication STA of claim 4 , wherein the circuitry is configured to transmit respective pilot carriers within the frequency allocation, the frequency allocation comprising a plurality of basic frequency units each including pilot locations, the respective pilot carriers being at respective ones of the pilot locations.

6 . The wireless communication STA of claim 5 , wherein one of the plurality of basic frequency units is around muted subcarriers, and wherein the pilot locations of the one of the plurality of basic frequency units around muted subcarriers are such that that the distance between the pilot locations are a same distance as between pilot locations of other basic frequency units of the plurality of basic frequency units that are not around muted subcarriers.

7 . The wireless communication STA of claim 5 , the circuitry further being configured to transmit the first pilot carrier in a pilot location of a lower basic frequency unit of the plurality of basic frequency units and to transmit the second pilot carrier in a pilot location of an upper basic frequency unit of the plurality of basic frequency units.

8 . The wireless communication STA of claim 5 , wherein the basic frequency units are one from the following group: 1.25 MHz, 2.03125 MHz, 2.5 MHz, 5 MHz, and 10 MHz.

9 . The wireless communication STA of claim 1 , wherein the lower subcarrier is in the lower one-third of the frequency allocation, and the higher subcarrier is in the higher one-third of the frequency allocation, and wherein the frequency allocation is one from the following group: 1.25 MHz, 2.03125 MHz, 2.5 MHz, 5 MHz, 10 MHz, 20 MHz, 40 MHz, 80 MHz, and 160 MHz.

10 . The wireless communication STA of claim 1 , wherein the lower subcarrier is a last subcarrier or a second to the last subcarrier of the lower subcarrier, and the higher subcarrier is a last subcarrier or a second to the last subcarrier of the higher subcarrier.

11 . The wireless communication STA of claim 1 , wherein the circuitry is further configured to:

transmit a third pilot carrier in the lower subcarrier of the frequency allocation simultaneously with the first pilot carrier; and

transmit a fourth pilot carrier in the higher subcarrier of the frequency allocation simultaneously with the second pilot carrier.

12 . The wireless communication STA of claim 11 , wherein the circuitry is further configured to:

transmit the first pilot carrier and the third pilot carrier in alternative time periods from the second pilot carrier and fourth pilot carrier.

13 . The wireless communication STA of claim 1 , wherein the circuitry is further configured to:

receive a fifth pilot from an access point (AP) within the frequency allocation;

receive a sixth pilot from the AP outside of the frequency allocation; and

use the fifth pilot and the sixth pilot to determine a clock of the AP.

14 . The wireless communication STA of claim 1 , the circuitry being configured to transmit the first pilot carrier and the second pilot carrier with a higher power than data simultaneously transmitted by the STA on a different subcarrier than the lower subcarrier and the higher subcarrier, wherein the higher power is one from the following group: approximately 10 percent higher power, approximately 20 percent higher power, approximately 30 percent higher power, approximately 40 percent higher power, approximately 50 percent higher power, approximately 60 percent higher power, approximately 70 percent higher power, approximately 80 percent higher power, approximately 90 percent higher power, and approximately 100 percent higher power.

15 . The wireless communication STA of claim 1 , wherein the frequency allocation comprises a plurality of smallest frequency allocations, and wherein each of the plurality of smallest frequency allocations includes pilot locations, and wherein the circuitry is further configured to:

transmit the first pilot carrier in a lowest or second lowest pilot location of a lowest smallest frequency allocation of the plurality of frequency allocations; and

transmit the second pilot carrier in a highest or second highest pilot location of a highest smallest frequency allocation of the plurality of frequency allocations.

16 . The wireless communication STA of claim 1 , wherein the circuitry is further configured to:

transmit in accordance with at least one of the following group: code division multiple access (CDMA) and time division multiple access (TDMA), and configured to alternate time periods with another wireless communication device to transmit the first pilot carrier and the second pilot carrier.

17 . The wireless communication STA of claim 1 , wherein the circuitry is further configured to:

transmit a third pilot carrier in a second spatial stream in the lower subcarrier of the frequency allocation; and

transmit a fourth pilot carrier in a second spatial stream in the upper subcarrier of the frequency allocation, wherein the first pilot carrier and the second pilot carrier are transmitted in a first spatial stream, and the third pilot carrier and the fourth pilot carrier are transmitted at a same frequency location as the first pilot carrier and the second pilot carrier, respectively, and wherein the wireless communication device is configured to transmit in accordance with multi-user multiple-input multiple-output (MU-MIMO).

18 . The wireless communications STA of claim 17 , wherein the circuitry is further configured to:

receive an indication of a sequence orthogonal to another sequence to be used by another wireless communication device; and

transmit the first pilot carrier, second pilot carrier, third pilot carrier, and fourth pilot carrier based on the sequenced.

19 . The wireless communications STA of claim 1 , further comprising memory coupled to the circuitry.

20 . The wireless communications STA of claim 19 , further comprising one or more antennas coupled to the circuitry.

21 . A method on a wireless communications station (STA), the method comprising:

receiving one or more packets in a transmit opportunity (TXOP) indicating a schedule for the wireless communication device to transmit;

transmitting a first pilot carrier in a lower subcarrier of a frequency allocation; and

transmitting a second pilot carrier in a higher subcarrier of the frequency allocation.

22 . The method of claim 21 , wherein the first pilot carrier and the second pilot carrier are transmitted simultaneously.

23 . The method of claim 21 , wherein the transmitting and receiving further comprises:

transmitting and receiving in accordance with Orthogonal Frequency Division Multiple Access (OFDMA).

24 . A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors to perform operations to transmit pilot carriers performed by a wireless communication device, the instructions to configure the one or more processors to cause the wireless communication device to:

receive one or more packets in a transmit opportunity (TXOP) indicating a schedule for the wireless communication device to transmit;

transmit a first pilot carrier in a lower subcarrier of a frequency allocation; and

transmit a second pilot carrier in a higher subcarrier of the frequency allocation.

25 . The non-transitory computer-readable storage medium of claim 24 , wherein the lower subcarrier is in the lower one-third of the frequency allocation, and the higher subcarrier is in the higher one-third of the frequency allocation, and wherein the frequency allocation is one from the following group: 1.25 MHz, 2.03125 MHz, 2.5 MHz, 5 MHz, 10 MHz, 20 MHz, 40 MHz, 80 MHz, and 16.