METHOD AND APPARATUS FOR SINGLE CARRIER SPREADING

• US 20090097533A1
• Filed: 10/09/2008
• Published: 04/16/2009
• Est. Priority Date: 11/16/2005
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Lakkis, Ismail
• Granted Patent: US 8,724,676 B2
• Time in Patent Office: Days
• US Class Current: 375/146
• CPC Class Codes: H04B 1/69 Spread spectrum techniques
• CPC Class Codes: H04B 1/707 using direct sequence modulation

Abstract

A wireless device comprises a code-assignment module configured for assigning Golay codes to be used for spreading, a spreading module configured for spreading data with the Golay codes to produce a signal, wherein the Golay codes are randomly used to spread the data, and a transmitter configured for transmitting the signal. The wireless device may transmit a first beacon signal via a set of quasi-omni beam patterns, and a second beacon signal via a set directional beam patterns. The first beacon signal has a first transmission rate that is higher than the second beacon signal'"'"'s the transmission rate. Extended Golay codes having zero periodic cross-correlation may be generated from a Golay code and a set of short sequences. A data block transmitted by the wireless device may comprise Golay codes and data portions, wherein every data portion is between two Golay codes and every Golay code is between two data portions.

Claims

1. A method of communication comprising:

assigning Golay codes to be used for spreading;

spreading data with the Golay codes to produce a signal, wherein the Golay codes are randomly used to spread the data; and

transmitting the signal.

2. The method recited in claim 1, wherein assigning comprises dynamically generating the Golay codes.

3. The method recited in claim 1, wherein the spreading provides frequency-spectrum flattening of the signal.

4. The method recited in claim 1, wherein the spreading reduces autocorrelation peaks of the signal when observed at a matched-filter receiver.

5. The method recited in claim 1, wherein the Golay codes belong to at least one pair of Golay complementary codes.

6. The method recited in claim 1, wherein assigning comprises generating the Golay codes by using a single delay vector for all of the Golay codes and a different seed vector for each of the Golay codes.

7. The method recited in claim 6, wherein generating the Golay codes comprises cyclically shifting at least one of the Golay codes.

8. The method recited in claim 1, wherein assigning comprises selecting the Golay codes from a set of Golay codes, said set of Golay codes being usable to spread data for communication via a plurality of links, and wherein:

the selected Golay codes are used for communication via a first link;

a subset of the unselected Golay codes are used for communication via a second link; and

the selected Golay codes and the unselected Golay codes associated with the second communication link have low cross correlation.

16. The apparatus recited in claim 1, wherein the means for assigning is configured for selecting the Golay codes from a set of Golay codes, said set of Golay codes being usable to spread data for communication via a plurality of links, and wherein:

the selected Golay codes are used for communication via a first link;

a subset of the unselected Golay codes are used for communication via a second link; and

the selected Golay codes and the unselected Golay codes associated with the second communication link have low cross correlation.

9. An apparatus for communication comprising:

means for assigning Golay codes to be used for spreading;

means for spreading data with the Golay codes to produce a signal, wherein the Golay codes are randomly used to spread the data; and

means for transmitting the signal.

10. The apparatus recited in claim 9, wherein the means for assigning is configured for dynamically generating the Golay codes.

11. The apparatus recited in claim 9, wherein the means for spreading provides frequency-spectrum flattening of the signal.

12. The apparatus recited in claim 9, wherein the means for spreading reduces autocorrelation peaks of the signal when observed at a matched-filter receiver.

13. The apparatus recited in claim 9, wherein the Golay codes belong to at least one pair of Golay complementary codes.

14. The apparatus recited in claim 9, wherein the means for assigning is configured for generating the Golay codes by using a single delay vector for all of the Golay codes and a different seed vector for each of the Golay codes.

15. The apparatus recited in claim 14, wherein generating the Golay codes comprises cyclically shifting at least one of the Golay codes.

17. An apparatus for communication comprising:

a code-assignment module configured for assigning Golay codes to be used for spreading;

a spreading module configured for spreading data with the Golay codes to produce a signal, wherein the Golay codes are randomly used to spread the data; and

a transmitter configured for transmitting the signal.

18. A machine-readable medium comprising instructions encoded thereon and executable to:

assign Golay codes to be used for spreading; and

spread data with the Golay codes to produce a signal, wherein the Golay codes are randomly used to spread the data.