New constrained blind adaptive receivers for DS-CDMA systems based on group constraints

In this work we develop a new framework for blind receivers based on the minimum variance (MV) and constant modulus (CM) criteria using a new set of constraints based on the knowledge of the spreading sequences of some users in the system. A family of blind stochastic gradient and recursive least- squares type algorithms for parameter estimation on the basis of the group constraints are derived. The performance of the proposed receivers is assessed through computer simulations. The results show that the proposed techniques outperform previously reported blind techniques with small additional computational requirements.