Pilot plan and design within OFDM/OFDMA wireless communications

Patent metadata

Field	Value
Publication number	US-9774428-B2
Application number	US-201615142431-A
Country	US
Kind code	B2
Filing date	Apr 29, 2016
Priority date	Jun 3, 2015
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

A wireless communication device (alternatively, device, WDEV, etc.) includes a processing circuitry configured to support communications with other WDEV(s) and to generate and process signals for such communications. In some examples, the device includes a communication interface and a processing circuitry, among other possible circuitries, components, elements, etc. to support communications with other WDEV(s) and to generate and process signals for such communications. A WDEV generates an orthogonal frequency division multiple access (OFDMA) frame that includes OFDMA symbol(s) that include a set of pilots based on an OFDMA sub-carrier plan. The WDEV transmits the OFDMA frame to other WDEV(s) for use by the other WDEV(s) to perform estimation of communication pathway(s) between the WDEV and the other WDEV(s) using the set of pilots. The OFDMA sub-carrier plan includes multiple OFDMA sub-carrier sub-plans of different sized RUs including pilots.

First claim

What is claimed is:

1. A wireless communication device comprising:
a processing circuitry configured to:
generate an orthogonal frequency division multiple access (OFDMA) frame that includes at least one OFDMA symbol that includes a set of pilots based on an OFDMA sub-carrier plan that is characterized by:
a first OFDMA sub-carrier sub-plan that includes a first plurality of resource units (RUs) of a first sub-carrier size and a first plurality of pilots at first locations that are substantially uniformly distributed within a plurality of OFDMA sub-carriers;
a second OFDMA sub-carrier sub-plan that includes a second plurality of RUs of a second sub-carrier size that is greater than the first sub-carrier size and a second plurality of pilots that includes a same number of pilots as the first plurality of pilots at second locations that are same as the first locations within the plurality of OFDMA sub-carriers based on a RU of the second plurality of RUs that is aligned in frequency within a communication channel with two adjacently-located RUs of the first plurality of RUs based on the OFDMA sub-carrier plan;
a third OFDMA sub-carrier sub-plan that includes a third plurality of RUs of a third sub-carrier size that is greater than the second sub-carrier size and a third plurality of pilots that includes fewer pilots than the second plurality of pilots at third locations that include a subset of the first locations within the plurality of OFDMA sub-carriers based on a RU of the third plurality of RUs that is aligned in frequency within the communication channel with a first RU of the second plurality of RUs on an end of the RU of the third plurality of RUs such that at least one null tone that is devoid of information is located between the first RU of the second plurality of RUs and a second RU of the second plurality of RUs based on the OFDMA sub-carrier plan; and
another OFDMA sub-carrier sub-plan that includes a single RU of another sub-carrier size that is greater than the third sub-carrier size and that spans bandwidth of the communication channel based on the OFDMA sub-carrier plan; and

transmit the OFDMA frame to at least one other wireless communication device for use by the at least one other wireless communication device to perform estimation of at least one communication pathway between the wireless communication device and the at least one other wireless communication device using the set of pilots.

2. The wireless communication device of claim 1 , wherein the plurality of OFDMA sub-carriers are included within the bandwidth of the communication channel that is 20 MHz, 40 MHz, 80 MHz, or 160 MHz.

3. The wireless communication device of claim 1 , wherein the processing circuitry is further configured to:
receive feedback from the at least one other wireless communication device that includes the estimation of the at least one communication pathway between the wireless communication device and the at least one other wireless communication device as performed by the at least one other wireless communication device using the set of pilots included within the OFDMA frame;
generate a beamformed OFDMA frame that includes at least one other OFDMA symbol based on the estimation of the at least one communication pathway between the wireless communication device and the at least one other wireless communication device; and
transmit the beamformed OFDMA frame to the at least one other wireless communication device.

4. The wireless communication device of claim 1 , wherein:
the first plurality of RUs of the first sub-carrier size includes 26 OFDMA sub-carriers;
the second plurality of RUs of the second sub-carrier size includes 52 OFDMA sub-carriers; and
the third plurality of RUs of the third sub-carrier size includes 106 OFDMA sub-carriers.

5. The wireless communication device of claim 1 , wherein:
the first OFDMA sub-carrier sub-plan includes the first plurality of RUs of the first sub-carrier size and at least one other RU that is one-half the first sub-carrier size that are distributed across the plurality of OFDMA sub-carriers;
the second OFDMA sub-carrier sub-plan includes the second plurality of RUs of the second sub-carrier size that is greater than the first sub-carrier size and at least one other RU that is one-half the second sub-carrier size that are distributed across the plurality of OFDMA sub-carriers; and
the third OFDMA sub-carrier sub-plan includes the third plurality of RUs of the third sub-carrier size that is greater than the second sub-carrier size and at least one other RU that is one-half the second sub-carrier size that are distributed across the plurality of OFDMA sub-carriers.

6. The wireless communication device of claim 1 further comprising:
a communication interface, coupled to the processing circuitry, that is configured to support communications within at least one of a satellite communication system, a wireless communication system, a wired communication system, a fiber-optic communication system, or a mobile communication system; and
the processing circuitry configured to transmit the OFDMA frame via the communication interface.

7. The wireless communication device of claim 1 further comprising:
an access point (AP), wherein the at least one other wireless communication device includes a wireless station (STA).

8. The wireless communication device of claim 1 further comprising:
a wireless station (STA), wherein the at least one other wireless communication device includes another STA.

9. A wireless communication device comprising:
a processing circuitry configured to:
generate an orthogonal frequency division multiple access (OFDMA) frame that includes at least one OFDMA symbol that includes a set of pilots based on an OFDMA sub-carrier plan that is characterized by:
a first OFDMA sub-carrier sub-plan that includes a first plurality of resource units (RUs) of a first sub-carrier size and a first plurality of pilots at first locations that are substantially uniformly distributed within a plurality of OFDMA sub-carriers of a communication channel that has a bandwidth of 20 MHz, 40 MHz, 80 MHz, or 160 MHz;
a second OFDMA sub-carrier sub-plan that includes a second plurality of RUs of a second sub-carrier size that is greater than the first sub-carrier size and a second plurality of pilots that includes a same number of pilots as the first plurality of pilots at second locations that are same as the first locations within the plurality of OFDMA; sub-carriers based on a RU of the second plurality of RUs that is aligned in frequency within the communication channel with two adjacently-located RUs of the first plurality of RUs based on the OFDMA sub-carrier plan;
a third OFDMA sub-carrier sub-plan that includes a third plurality of RUs of a third sub-carrier size that is greater than the second sub-carrier size and a third plurality of pilots that includes fewer pilots than the second plurality of pilots at third locations that include a subset of the first locations within the plurality of OFDMA; sub-carriers based on a RU of the third plurality of RUs that is aligned in frequency within the communication channel with a first RU of the second plurality of RUs on an end of the RU of the third plurality of RUs such that at least one null tone that is devoid of information is located between the first RU of the second plurality of RUs and a second RU of the second plurality of RUs based on the OFDMA sub-carrier plan; and
another OFDMA sub-carrier sub-plan that includes a single RU of another sub-carrier size that is greater than the third sub-carrier size and that spans the bandwidth of the communication channel based on the OFDMA sub-carrier plan; and

transmit the OFDMA frame to at l

Assignees

• Broadcom Corp
• Avago Technologies General Ip

Inventors

• Montreuil Leo
• Porat Ron

Classifications

• 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

• H04B7/0452

  Multi-user MIMO systems · CPC title

• H04L5/0007

  the frequencies being orthogonal, e.g. OFDM(A) or DMT · CPC title

• H04L12/2854

  Wide area networks, e.g. public data networks · CPC title

• H04B7/0408

  using two or more beams, i.e. beam diversity · CPC title