Spread-spectrum transceiver
View Patent ↗An assembly of simultaneously transmitted electrically generated signals, which contains a subset of binary spreading-code sequences that are members of a larger set of binary spreading-code sequences available to a particular node of a multi-node communication network. All sequences in the set of spreading-code sequences available to the particular node of the network can be generated by the same configuration of two linear-feedback binary shift registers, where feedback taps of the two linear-feedback binary shift registers correspond to primitive polynomials of the same degree over GF( 2 ), the field of two elements.
1. A transmitting apparatus for transmitting information in a multi-node communication network, comprising:
an almost orthogonal code sequence generator that generates a set of almost orthogonal code sequences and generates an almost orthogonal code sequence by combining contents of specified stages of a first shift register with contents of specified stages of a second shift register, said set of almost orthogonal code sequences being selected from a plurality of subsets of a set of almost orthogonal code sequences associated with the transmitting apparatus; and
a transmitter for simultaneously transmitting a first I signal and a first Q signal during a first time interval and simultaneously transmitting a second I signal and a second Q signal during a second time interval, said first I signal and said first Q signal including said almost orthogonal code sequence and a first subset of said set of almost orthogonal code sequences, and said second I signal and said second Q signal including said almost orthogonal code sequence and a second subset of said almost orthogonal code sequences not identical with said first subset, wherein at least one of said first and second subsets from the set of almost orthogonal code sequences includes more than one almost orthogonal code sequence.
2. The transmitting apparatus of claim 1 wherein the cross-correlation between any two distinct sequences from said set of almost orthogonal code sequences is zero.
3. The transmitting apparatus of claim 2 wherein said almost orthogonal code sequence is a Gold code.
4. The transmitting apparatus of claim 1 wherein said first and second I signals and said first and second Q signals are configured to carry data or control information.
5. The transmitting apparatus of claim 1 wherein said first subset contains two or more code sequences.
6. The transmitting apparatus of claim 1 wherein said first and second subsets each contains two or more code sequences.
7. The transmitting apparatus of claim 1 wherein a code sequence from said first subset is based upon a particular data rate.
8. The transmitting apparatus of claim 1 , further comprising:
a modulator that modulates said first and second I signals and said first and second Q signals onto corresponding carriers of the same frequency having different phases.
9. The transmitting apparatus of claim 8 , wherein said modulator uses phase shift keying.
10. A transmitting apparatus for transmitting information in a multi-node communication network, comprising:
an almost orthogonal code sequence generator that generates a set of almost orthogonal code sequences and an almost orthogonal code sequence, said set of almost orthogonal code sequences being selected from a plurality of subsets of a set of almost orthogonal code sequences associated with the transmitting apparatus; and
a transmitter for simultaneously transmitting first signals during a first time interval and simultaneously transmitting second signals during a second time interval, said first signals including said almost orthogonal code sequence and a first subset of said set of almost orthogonal code sequences and said second signals including said almost orthogonal code sequence and a second subset of said set of almost orthogonal code sequences not identical with said first subset, wherein at least one of said first and second subsets from the set of almost orthogonal code sequences includes more than one almost orthogonal code sequence.
11. The transmitting apparatus of claim 10 wherein said first subset contains two or more code sequences.
12. The transmitting apparatus of claim 10 wherein said first subset contains two or more code sequences and said second subset contains two or more code sequences.
13. The transmitting apparatus of claim 10 wherein a code sequence from said first subset is based upon a particular data rate.
14. The transmitting apparatus of claim 10 wherein a code sequence from said first subset is based upon a first data rate and a code sequence from said second subset is based upon a second data rate different from said first data rate.
15. The transmitting apparatus of claim 10 , further comprising:
a modulator that modulates said first signals and said second signals onto two corresponding carriers of the same frequency.
16. The transmitting apparatus of claim 15 , wherein said modulator uses phase shift keying.
17. A method for transmitting information in a multi-node communication network, comprising:
generating a set of almost orthogonal code sequences, said set of almost orthogonal code sequences being selected from a plurality of subsets of a set of almost orthogonal code sequences;
generating an almost orthogonal code sequence by combining contents of specified stages of a first shift register with contents of specified stages of a second shift register; and
simultaneously transmitting a first I signal and a first Q signal during a first time interval and simultaneously transmitting a second I signal and a second Q signal during a second time interval, said first I signal and said first Q signal including said almost orthogonal code sequence and a first subset of said set of almost orthogonal code sequences, and said second I signal and said second Q signal including said almost orthogonal code sequence and a second subset of said almost orthogonal code sequences not identical with said first subset, wherein at least one of said first and second subsets from the set of almost orthogonal code sequences includes more than one almost orthogonal code sequence.
18. The method of claim 17 wherein the cross-correlation between any two distinct sequences from said set of almost orthogonal code sequences is zero.
19. The method of claim 17 wherein said almost orthogonal code sequence is a Gold code.
20. The method of claim 17 wherein said first and second I signals and said first and second Q signals are configured to carry data or control information.
21. The method of claim 17 wherein said first subset contains two or more code sequences.
22. The method of claim 17 wherein said first and second subsets each contains two or more code sequences.
23. The method of claim 17 wherein a code sequence from said first subset is based upon a particular data rate.
24. The method of claim 17 , further comprising the step of:
modulating said first and second I signals and said first and second Q signals onto corresponding carriers of the same frequency having different phases.
25. The method of claim 17 , wherein said modulating step uses phase shift keying.
26. A method for communicating information in a multi-node communication network, comprising:
generating a set of almost orthogonal code sequences, said set of almost orthogonal code sequences being selected from a plurality of subsets of a set of almost orthogonal code sequences;
generating an almost orthogonal code sequence; and
simultaneously transmitting first signals during a first time interval and simultaneously transmitting second signals during a second time interval, said first signals including said almost orthogonal code sequence and a first subset of said set of almost orthogonal code sequences and said second signals including said almost orthogonal code sequence and a second subset of said set of almost orthogonal code sequences not identical with said first subset, wherein at least one of said first and second subsets from the set of almost orthogonal code sequences includes more than one almost orthogonal code sequence.
27. The method of claim 26 wherein said first subset contains two or more code sequences.
28. The method of claim 26 wherein said first subset contains two or more code sequences and said second subset contains two or more code sequences.
29. The method of claim 26 wherein a code sequence from said first subset is based upon a particular data rate.
30. The method of claim 26 wherein a code sequence from said first subset is based upon a first data rate and a code sequence from said second subset is based upon a second data rate different from said first data rate.
31. The method of claim 26 , further comprising the step of:
modulating said first signals and said second signals onto two corresponding carriers of the same frequency.
32. The method of claim 31 , wherein said modulating step uses phase shift keying.