Distance-Optimal Oversaturated CDMA Signature Ensemble

A method of increasing the capacity of synchronous DS-CDMA beyond the signal space dimension is called oversaturation. When the number of users exceeds the signal space dimension, it does not in principle prohibit the maximization of minimum Euclidean distance between the points of a group signal constellation up to the optimum achieved with orthogonal users´ signatures. Previously reported construction of distance-optimal signature ensembles was limited to only signal space dimensions equal to the natural power of four. This paper presents a generalization of such a method to arbitrary signal space dimensions. Necessary condition of presenting binary antipodal alphabet in the oversaturated ensembles of this kind is also discussed.