Minimum variance multi-user detection with optimum subband decomposition over multipath channels

This paper presents a linear constrained minimum variance multiuser detection (MUD), which makes full use of the available spreading sequences of the users as well as the path delays of the corresponding incoming rays in the construction of the constraint matrix. Next, the design of a statistical optimum filter bank in combination with the developed minimum variance MUD with the generalized sidelobe canceller (GSC) as the underlying structure is addressed. The determination of the filter bank coefficients, however, calls for computationally demanding nonlinear programming. To alleviate the computational overhead, an iterative procedure is also proposed, which solves the Rayleigh quotient in each iteration. Furnished simulations show that the new scheme yields superior performance compared with previous works.