Low complexity k-best based iterative receiver for MIMO systems

Iterative receiver combining multiple-input multiple-output (MIMO) detection with channel decoding is an attractive solution to greatly improve the error rate performance of wireless communication systems. However, such iterative process poses significant challenges for efficient receiver design. In this paper, a modification of soft-input soft-output K-Best decoder is proposed to provide high throughput with low complexity. Moreover, the convergence of combining sphere decoder based detection algorithms with LTE turbo decoder is analyzed with the help of EXtrinsic Information Transfer (EXIT) charts. An optimized scheduling of the number of iterations is therefore proposed. Simulation results show that the proposed decoder and the new schedule achieve almost the same performance compared to the conventional schedule with a large saving in computational complexity.