Patent ID: 7505506

Claim:
A method implemented in a system for generating a composite signal comprising the steps of: (a) generating a plurality of sub-carriers, each sub-carrier having a different frequency position in a frequency spectrum; (b) generating a plurality of codes; (c) forming a plurality of code combinations from the plurality of codes generated in step (b), wherein a code combination is comprised of at least two codes from the plurality of codes; (d) first modulating each sub-carrier using a respective one of the code combinations formed in step (c) to form a plurality of modulated sub-carriers; and (e) second modulating in-phase and quadrature components of a base carrier using the plurality of modulated sub-carriers to form the composite signal having multiple carriers; step (c) includes forming the following code combinations: CC 1 (t), CC 2 (t), CC 3 (t) . . . CC N (t) where N is the number of code combinations, N=2 or more, and CC i (t) is a code combination at frequency position ƒ o +ƒ i ; and ∑ i = 1 N ⁢ ⁢ CC i 2 ⁡ ( t ) = constant and CC i ⁡ ( t ) ⁢ CC j ⁡ ( t ) = { const , i = j 0 , i ≠ j .