A* Algorithm Inspired Memory-Efficient Detection for MIMO Systems

Implementation of a best-first detection algorithm for multiple-input multiple-output (MIMO) systems requires large amounts of memory especially in large systems with high-order modulation. In this letter, we propose modified best-first detection algorithms in which the order of nodes is determined by both the original cost and the estimated future cost associated with each node, as inspired by an improved shortest path algorithm (A* algorithm). The modified algorithms maintain the detection optimality, reduce the memory requirement and sorting complexity, and achieve improved detection performance in memory-constrained scenarios.