Patent ID: 7349459

Claim:
A method of processing a received signal, comprising: detecting within said received signal a plurality of possible symbols (d k (i)) transmitted by or for a plurality K of users, each of the plurality of possible symbols belonging to a modulation constellation and being the subject of a spectral spreading by a spreading sequence (s k (t)), said step of detecting comprising substeps of: filtering said received signal, said filtering step adapted for supplying a complex vector characteristic of said received signal, and including decomposing said complex vector into a real vector (y R (i)) and an imaginary vector (y I (i)); searching separately for at least a closest neighbor of the real vector and a closest neighbor of the imaginary vector within a respective real and imaginary lattice of points (Λ, Ω) corresponding to said modulation constellation; and estimating the transmitted symbols from components of said closest neighbor of the real vector and the closest neighbor of the imaginary vector so as to produce a vector of estimated symbols, wherein the step of searching is limited to a first set of points in the real lattice belonging to a first predetermined zone (Σ R ) around the real vector and a second set of points in the imaginary lattice belonging to a second predetermined zone (Σ I ) around the imaginary vector.