MATCHED FILTER FOR SCALABLE SPREAD SPECTRUM COMMUNICATIONS SYSTEMS

• US 20060245481A1
• Filed: 06/28/2006
• Published: 11/02/2006
• Est. Priority Date: 09/24/2003
• Status: Active Grant

• Current Assignee: Recon Dynamics LLC (Tricon Sales LLC)
• Original Assignee: S5 Wireless, Inc. (Tricon Sales LLC)
• Inventors: Prestwich, Sy, Bevan, Scott, Ostermiller, Dirk, Dobson, W. Kurt
• Granted Patent: US 7,280,579 B2
• Time in Patent Office: Days
• US Class Current: 375/152
• CPC Class Codes: H04B 1/7093 Matched filter type
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04B 2201/70707 Efficiency-related aspects
• CPC Class Codes: H04J 13/0022 PN, e.g. Kronecker

Abstract

A spread spectrum communications system using long, scalable PN sequences to achieve variable communication rates using a low-complexity and scalable matched filter architecture to provide a large processing gain, robust recovery of multiple devices in long reach, high ambient-noise environments.

Claims

1-10. -10. (canceled)

11. A transmitter for a spread spectrum communications system, comprising:

a data source;

a first multiplier/mixer spreading data from said data source with a first pseudo noise source;

a second multiplier/mixer spreading data from said first mixer with a second pseudo noise source; and

an RF transmitter;

12. A spread spectrum communications system, as recited in claim 11, wherein said first pseudo noise source provides a variable length code sequence.

13. A spread spectrum communications system, as recited in claim 11, wherein said first pseudo noise source provides a fixed length code sequence.

14. A spread spectrum communications system, as recited in claim 11, wherein said second pseudo noise source provides a fixed length code sequence.

15. A spread spectrum communications system, as recited in claim 11, wherein said second pseudo noise source provides a variable length code sequence.

16. A spread spectrum communications system, as recited in claim 11, wherein said first multiplier mixer spreads said data from said data source with a variable length PN code.

17. A spread spectrum communications system, as recited in claim 11, wherein said first multiplier mixer spreads said data from said data source with a fixed length PN code.

18. A spread spectrum communications system, as recited in claim 11, wherein said second multiplier mixer spreads said data from said first mixer with a fixed length PN code.

19. A spread spectrum communications system, as recited in claim 11, wherein said second multiplier mixer spreads said data from said first mixer with a variable length PN code.

20. A receiver for a spread spectrum communications system, comprising:

an RF receiver;

a first matched filter receiving data from said RF receiver;

a plurality of phase/frequency shifters, receiving a signal from said first matched filter;

a plurality of second matched filters receiving data from said plurality of phase/frequency shifters; and

an equalizer/decoder receiving signals from said plurality of second matched filters.

21. A spread spectrum communications system, as recited in claim 20, wherein said second matched filters are correlated to a first pseudo noise source.

22. A spread spectrum communications system, as recited in claim 20, wherein a first pseudo noise source and a second pseudo noise source may be scaled to longer or shorter fixed or variable code lengths to optimize variables such as connection quality, system complexity, overall implementation cost and service “

classes”

of devices.