Application of Semi Definite Relaxation and Variable Neighborhood Search for Multiuser Detection in Synchronous CDMA
In this article, a detection strategy based on variable neighborhood search (VNS) and semidefinite relaxation of the multiuser model maximum likelihood (ML) is investigated. The VNS method provides a good method for solving the ML problem while keeping the integer constraints. A SDP relaxation is used as an efficient way to generate an initial solution in a limited amount of time, in particular using early termination. The SDP resolution tool used is the spectral bundle method developed by Helmberg. We show that using VNS can result in a better error rate, but at a cost of calculation time. (C) 2009 Wiley Periodicals, Inc. NETWORKS, Vol. 55(3), 187-193 2010
variable neighborhood search semidefinite programming multiuser detection problem