Group-Optimal Linear Space-Time Multiuser Detection

Multiuser detection (MUD) techniques are known to improve the performance of CDMA cellular communication systems. This performance improvement usually comes at a large computational cost. To reduce the complexity, it has been proposed recently to exploit the spatial dimension by grouping users in clusters and apply MUD individually to each group. This approach leads to a potentially significant complexity reduction, at a marginal cost in performance. In this work we propose a new space-time receiver structure based on the group-optimal MMSE linear detector. The numerical results show that the proposed technique performs close to the optimal full space-time linear MMSE MUD receiver but with a significantly lower complexity