Short training field (STF) for use within single user, multiple user, multiple access, and/or MIMO wireless communications

• US 20120269125A1
• Filed: 04/23/2012
• Published: 10/25/2012
• Est. Priority Date: 04/24/2011
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Porat, Ron, Zheng, Jun
• Granted Patent: US 9,113,490 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 27/2603 Signal structure ensuring backward compatibility with legacy system
• CPC Class Codes: H04L 27/26035 Maintenance of orthogonality, e.g. for signals exchanged between cells or users, or by using covering codes or sequences using different training sequence per antenna H04B7/0684; code allocation H04J13/16
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2618 Reduction thereof using auxiliary subcarriers
• CPC Class Codes: H04L 27/2666 Acquisition of further OFDM parameters, e.g. bandwidth, subcarrier spacing, or guard interval length
• CPC Class Codes: H04W 52/18 TPC being performed according to specific parameters
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

Short training field (STF) for use within single user, multiple user, multiple access, and/or MIMO wireless communications. An STF design as is made such that the power associated with the tone indices at the edges of the STF design is relatively less than the power associated with the tone indices more centrally located within the STF design. Also, when multiple respective operational modes are supported (e.g., 1 MHz and 2 MHz), the respective STF designs corresponding to those respective operational modes have a great deal of similarity. For example, the respective STF designs for different respective operational modes may have certain common STF tone indices among those respective STF designs.

Claims

1. An apparatus, comprising:

a baseband processing module selectively to generate a packet having a selected packet type of a plurality of packet types, wherein;

each of the plurality of packet types having a respective short training field (STF) sequence with a respective peak to average power ratio (PAPR) less than a threshold and having a respective tone index with edge tone power relatively lower than central tone power such that magnitude of edge tone values being one-half magnitude of central tone values; and

a first tone index of a first of the plurality of packet types being a subset of a second tone index of a second of the plurality of packet types;

a physical layer (PHY) to support communications with the at least one additional apparatus in accordance with a plurality of channel bandwidths such that each of the plurality of packet types respectively corresponding to a respective one of the plurality of channel bandwidths; and

at least one antenna to transmit a signal corresponding to the packet to at least one additional apparatus.

2. The apparatus of claim 1, wherein:

each respective tone index of each of the plurality of packet types including a plurality of tones having at least indices [−

12;

4;

−

4, 4;

4;

12] or [−

12 −

8 −

4 4 8 12].

3. The apparatus of claim 1, wherein:

a respective STF sequence of a first of the plurality of packet types being a 32 fast Fourier transform (FFT) STF sequence;

a respective STF sequence of a second of the plurality of packet types being a 64 FFT STF sequence; and

each respective STF sequence of each of the plurality of packet types having every 4^th tone modulated.

4. The apparatus of claim 1, wherein:

a first of the plurality of channel bandwidths being 1 MHz; and

a second of the plurality of channel bandwidths being 2 MHz.

5. The apparatus of claim 1, wherein:

the apparatus is an access point (AP); and

the at least one additional apparatus is a wireless station (STA).

6. An apparatus, comprising:

a baseband processing module selectively to generate a packet having a selected packet type of a plurality of packet types, wherein each of the plurality of packet types having a respective short training field (STF) sequence with a respective peak to average power ratio (PAPR) less than a threshold and having a respective tone index such that at least some of the tones have non-equal tone power;

a physical layer (PHY) to support communications with the at least one additional apparatus in accordance with a plurality of channel bandwidths such that each of the plurality of packet types respectively corresponding to a respective one of the plurality of channel bandwidths; and

at least one antenna to transmit a signal corresponding to the packet to at least one additional apparatus.

7. The apparatus of claim 6, wherein:

a first tone index of a first of the plurality of packet types being a subset of a second tone index of a second of the plurality of packet types.

8. The apparatus of claim 6, wherein:

each respective tone index of each of the plurality of packet types including a plurality of tones having at least indices [−

12;

4;

−

4, 4;

4;

12] or [−

12 −

8 −

4 4 8 12]; and

at least one respective tone index of the plurality of packet types having edge tone power relatively lower than central tone power.

9. The apparatus of claim 6, wherein:

a respective STF sequence of a first of the plurality of packet types being a 32 fast Fourier transform (FFT) STF sequence; and

a respective STF sequence of a second of the plurality of packet types being a 64 FFT STF sequence.

10. The apparatus of claim 6, wherein:

a first of the plurality of channel bandwidths being 1 MHz; and

a second of the plurality of channel bandwidths being 2 MHz.

11. The apparatus of claim 6, wherein:

within each respective tone index, magnitude of edge tone values being one-half magnitude of central tone values.

12. The apparatus of claim 6, wherein:

each respective STF sequence of each of the plurality of packet types having every 4^th tone modulated.

13. The apparatus of claim 6, wherein:

the apparatus is an access point (AP); and

the at least one additional apparatus is a wireless station (STA).

14. A method for operating a communication device, the method comprising:

selectively generating a packet having a selected packet type of a plurality of packet types, wherein each of the plurality of packet types having a respective short training field (STF) sequence with a respective peak to average power ratio (PAPR) less than a threshold and having a respective tone index such that at least some of the tones have non-equal tone power;

operating a physical layer (PHY) of the communication device to support communications with at least one additional communication device in accordance with a plurality of channel bandwidths such that each of the plurality of packet types respectively corresponding to a respective one of the plurality of channel bandwidths; and

via at least one antenna of the communication device, transmitting a signal corresponding to the packet to at least one additional communication device.

15. The method of claim 14, wherein:

a first tone index of a first of the plurality of packet types being a subset of a second tone index of a second of the plurality of packet types.

16. The method of claim 14, wherein:

each respective tone index of each of the plurality of packet types including a plurality of tones having at least indices [−

12;

4;

−

4, 4;

4;

12] or [−

12 −

8 −

4 4 8 12]; and

at least one respective tone index of the plurality of packet types having edge tone power relatively lower than central tone power.

17. The method of claim 14, wherein:

a respective STF sequence of a first of the plurality of packet types being a 32 fast Fourier transform (FFT) STF sequence;

a respective STF sequence of a second of the plurality of packet types being a 64 FFT STF sequence; and

each respective STF sequence of each of the plurality of packet types having every 4^th tone modulated.

18. The method of claim 14, wherein:

a first of the plurality of channel bandwidths being 1 MHz; and

a second of the plurality of channel bandwidths being 2 MHz.

19. The method of claim 14, wherein:

within each respective tone index, magnitude of edge tone values being one-half magnitude of central tone values.

20. The method of claim 14, wherein:

the communication device is an access point (AP); and

the at least one additional communication device is a wireless station (STA).