Preamble design within wireless communications

• US 9,774,378 B2
• Filed: 11/23/2015
• Issued: 09/26/2017
• Est. Priority Date: 04/24/2011
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Porat, Ron
• Primary Examiner(s): Qureshi, Afsar M
• Application Number:
  US14/948,604
• Publication Number:
  US 20160080056A1
• Time in Patent Office: 673 Days
• Field of Search: 370312, 370329
• CPC Class Codes: H04B 7/06 at the transmitting station
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04L 27/26136 Pilot sequence conveying additional information
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A wireless communication device (alternatively, device) includes a processor configured to support communications with other wireless communication device(s) and to generate and process signals for such communications. In some examples, the device includes a communication interface and a processor, among other possible circuitries, components, elements, etc. to support communications with other wireless communication device(s) and to generate and process signals for such communications. The device is configured to generate OFDM/A packets having certain characteristics based on different packet formats. For example, a first OFDM/A packet has first characteristic(s) based on a first packet format, a second OFDM/A packet has second characteristic(s) based on a second packet format, and so on. A receiver device is configured to process such OFDM/A packets to determine characteristic(s) thereof to determine, identify, classify, etc. their respective packet formats so that the OFDM/A packets can be properly and appropriately processed based on their particular packet formats.

Claims

1. A wireless communication device comprising:

a processor configured to;

identify a selected orthogonal frequency division multiplexing (OFDM) packet format from a first OFDM packet format, a second OFDM packet format, and a third OFDM packet format;

generate, based on the selected OFDM packet format, an OFDM packet that includes a preamble, wherein the preamble includes a first signal field (SIG) that is followed by a second SIG that is followed by a third SIG, wherein the first SIG is based on a first communication protocol, and the second SIG and the third SIG are based on a second communication protocol;

generate the preamble, when the selected OFDM packet format is the first OFDM packet format, such that the first SIG includes first content;

generate the preamble, when the selected OFDM packet format is the second OFDM packet format, such that the second SIG includes second content, the second SIG has a first phase, and the third SIG has a second phase that is 90 degrees phase shifted from the first phase;

generate the preamble, when the selected OFDM packet format is the third OFDM packet format, such that the second SIG includes the second content, and both the second SIG and the third SIG have the first phase; and

transmit the OFDM packet to another wireless communication device.

2. The wireless communication device of claim 1, wherein the processor is further configured to:

generate, based on the selected OFDM packet format, the OFDM packet, wherein the first SIG is adjacently preceded by a copy of the first SIG.

3. The wireless communication device of claim 2, wherein the processor is further configured to:

generate the OFDM packet to include a short training field (STF) that is adjacently followed by a long training field (LTF) that is adjacently followed by the copy of the first SIG that is adjacently followed by the first SIG that is adjacently followed by the second SIG that is adjacently followed by the third SIG, wherein the STF, the LTF, and the first SIG are based on the first communication protocol, wherein the second SIG and the third SIG are based on the second communication protocol that is different than the first communication protocol.

4. The wireless communication device of claim 1, wherein the processor is further configured to:

generate the OFDM packet to include the preamble followed by data, wherein a first portion of the preamble is based on the first communication protocol and includes the first SIG that is adjacently preceded by a copy of the first SIG, wherein a second portion of the preamble is based on the second communication protocol and includes the second SIG and the third SIG.

5. The wireless communication device of claim 1, wherein the processor is further configured to:

generate the preamble such that the first SIG is followed by the second SIG is followed by the third SIG, wherein the first SIG includes information that specifies modulation coding set (MCS) of at least one of the second SIG or the third SIG.

6. The wireless communication device of claim 1 further comprising:

a communication interface, the processor and the communication interface configured to transmit the OFDM packet to the another wireless communication device, wherein;

the first communication protocol is a first IEEE 802.11 communication protocol; and

the second communication protocol is a second IEEE 802.11 communication protocol that is a legacy IEEE 802.11 communication protocol version to the first IEEE 802.11 communication protocol.

7. The wireless communication device of claim 1 further comprising:

an access point (AP), wherein the another wireless communication device is a wireless station (STA).

8. The wireless communication device of claim 1 further comprising:

a wireless station (STA), wherein the another wireless communication device is an access point (AP).

9. A wireless communication device comprising:

a processor configured to;

identify a selected orthogonal frequency division multiplexing (OFDM) packet format from a first OFDM packet format, a second OFDM packet format, and a third OFDM packet format;

generate, based on the selected OFDM packet format, an OFDM packet that includes a preamble, wherein the preamble includes a short training field (STF) that is adjacently followed by a long training field (LTF) that is adjacently followed a first signal field (SIG) that is adjacently followed by a copy of the first SIG that is adjacently followed a second SIG that is adjacently followed by a third SIG, wherein the STF, the LTF, and first SIG are based on a first communication protocol, wherein the second SIG and the third SIG are based on a second communication protocol, wherein the first SIG includes information that specifies modulation coding set (MCS) of at least one of the second SIG or the third SIG;

generate the preamble, when the selected OFDM packet format is the first OFDM packet format, such that the first SIG includes first content;

generate the preamble, when the selected OFDM packet format is the second OFDM packet format, such that the second SIG includes second content, the second SIG has a first phase, and the third SIG has a second phase that is 90 degrees phase shifted from the first phase;

generate the preamble, when the selected OFDM packet format is the third OFDM packet format, such that the second SIG includes the second content, and both the second SIG and the third SIG have the first phase; and

transmit the OFDM packet to another wireless communication device.

10. The wireless communication device of claim 9, wherein the processor is further configured to:

generate the OFDM packet to include the preamble followed by data, wherein a first portion of the preamble is based on the first communication protocol and includes the STF that is adjacently followed by the LTF that is adjacently followed by the first SIG that is adjacently followed by the copy of the first SIG, wherein a second portion of the preamble is based on the second communication protocol and includes the second that is adjacently followed by the third SIG.

11. The wireless communication device of claim 9, wherein:

the first communication protocol is a first IEEE 802.11 communication protocol; and

the second communication protocol is a second IEEE 802.11 communication protocol that is a legacy IEEE 802.11 communication protocol version to the first IEEE 802.11 communication protocol.

12. The wireless communication device of claim 9, wherein the processor is further configured to:

an access point (AP), wherein the another wireless communication device is a wireless station (STA).

13. The wireless communication device of claim 9 further comprising:

a wireless station (STA), wherein the another wireless communication device is an access point (AP).

14. A method for execution by a wireless communication device, the method comprising:

identifying a selected orthogonal frequency division multiplexing (OFDM) packet format from a first OFDM packet format, a second OFDM packet format, and a third OFDM packet format;

generating, based on the selected OFDM packet format, an OFDM packet that includes a preamble, wherein the preamble includes a first signal field (SIG) that is followed by a second SIG that is followed by a third SIG, wherein the first SIG is based on a first communication protocol, and the second SIG and the third SIG are based on a second communication protocol;

generating the preamble, when the selected OFDM packet format is the first OFDM packet format, such that the first SIG includes first content;

generating the preamble, when the selected OFDM packet format is the second OFDM packet format, such that the second SIG includes second content, the second SIG has a first phase, and the third SIG has a second phase that is 90 degrees phase shifted from the first phase;

generating the preamble, when the selected OFDM packet format is the third OFDM packet format, such that the second SIG includes the second content, and both the second SIG and the third SIG have the first phase; and

transmitting, via a communication interface of the wireless communication device, the OFDM packet to another wireless communication device.

15. The method of claim 14 further comprising:

generating, based on the selected OFDM packet format, the OFDM packet, wherein the first SIG is adjacently preceded by a copy of the first SIG.

16. The method of claim 15 further comprising:

generating the OFDM packet to include a short training field (STF) that is adjacently followed by a long training field (LTF) that is adjacently followed by the copy of the first SIG that is adjacently followed by the first SIG that is adjacently followed by the second SIG that is adjacently followed by the third SIG, wherein the STF, the LTF, and the first SIG are based on the first communication protocol, wherein the second SIG and the third SIG are based on the second communication protocol that is different than the first communication protocol.

17. The method of claim 14 further comprising:

generating the OFDM packet to include the preamble followed by data, wherein a first portion of the preamble is based on the first communication protocol and includes the first SIG that is adjacently preceded by a copy of the first SIG, wherein a second portion of the preamble is based on the second communication protocol and includes the second SIG and the third SIG.

18. The method of claim 14 further comprising:

generating the preamble such that the first SIG is followed by the second SIG is followed by the third SIG, wherein the first SIG includes information that specifies modulation coding set (MCS) of at least one of the second SIG or the third SIG.

19. The method of claim 14, wherein:

the first communication protocol is a first IEEE 802.11 communication protocol; and

the second communication protocol is a second IEEE 802.11 communication protocol that is a legacy IEEE 802.11 communication protocol version to the first IEEE 802.11 communication protocol.

20. The method of claim 14, wherein the wireless communication device is a wireless station (STA), and the another wireless communication device is an access point (AP).