A hypothesis testing approach to blind DS-CDMA user identification and detection via code-constrained successive cancellation

A code-constrained inverse filter criterion based approach was recently presented by J.K. Tugnait and Tongtong Li (see IEEE Trans. Sig. Processing, vol.SP-49, p.1300-9, 2001) for blind detection of a desired user in asynchronous short-code DS-CDMA (direct sequence code division multiple access) systems over multipath channels. The method proposed therein works well for low-to-moderate loading; however, it can converge to an undesired user under high loading. We augment this method with a binary hypothesis testing approach for extracted user identification (whether the desired user is acquired/extracted) and for successive user cancellation (if an undesired user is extracted, cancel its contribution and repeat). An illustrative simulation example is presented.