Real-time algorithms and architectures for multiuser channel estimation and detection in wireless base-station receivers

This paper presents algorithms and architecture designs that can meet real-time requirements of multiuser channel estimation and detection in future CDMA-based wireless base-station receivers. Sophisticated algorithms proposed to implement multiuser channel estimation and detection make their real-time implementation difficult on current Digital Signal Processor (DSP)-based receivers. A maximum-likelihood based multiuser channel estimation scheme requiring matrix inversions is redesigned from an implementation perspective for a reduced complexity, iterative scheme with a simple fixed-point VLSI architecture. A reduced-complexity, bit-streaming multiuser detection algorithm that avoids the need for multishot detection is also developed for a simple, pipelined VLSI architecture. Thus, we develop real-time solutions for multiuser channel estimation and detection for third generation wireless systems by (1) designing the algorithms from a fixed-point implementation perspective, without significant loss in error rate performance, (2) task partitioning and (3) designing bit-streaming fixed-point VLSI architectures that explore pipelining, parallelism and bit-level computations to achieve real-time with minimum area overhead.