Low Complexity, Quasi-Optimal MIMO Detectors for Iterative Receivers

• Published in: IEEE transactions on wireless communications Vol. 9; no. 10; pp. 3166 - 3177
• Main Authors: Tomasoni, Alessandro, Siti, Massimiliano, Ferrari, Marco, Bellini, Sandro
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.10.2010; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Business and industry local networks; Complexity theory; Decoding; Detection, estimation, filtering, equalization, prediction; Detectors; Exact sciences and technology; EXIT charts; Information, signal and communications theory; MAP estimation; MIMO; MIMO systems; Modulation, demodulation; Networks and services in france and abroad; OFDM; Receivers; Signal and communications theory; Signal, noise; sphere detection; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Teleprocessing networks. Isdn; Transmission and modulation (techniques and equipments); Transmitting antennas; turbo detection; Performance evaluation; MIMO system; MAP estimation; Hardware description languages; Wireless LAN; turbo detection; Parameter estimation; Quadrature amplitude modulation; Error estimation; Spatial correlation; Wireless telecommunication; Iterative method; Optimal detection; Information transmission; Implementation; sphere detection; EXIT charts; MIMO systems; Frequency selection; Channel estimation; A posteriori estimation; Deterministic approach
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/TWC.2010.090210.091357

We propose a novel family of Soft-Input Soft-Output detectors for iterative, point-to-point, MIMO receivers. Compared to the optimal Maximum A Posteriori receiver, low complexity is achieved restricting the detector search to small subsets of the entire QAM hyper-symbol constellation, through simple criteria. These criteria are applied to an improved version of the non-iterative Layered ORthogonal lattice Detector. We show that, notwithstanding the suboptimal low-complexity implementation, this detector approaches the EXtrinsic Information Transfer of the MAP detector. Therefore, when included in an iterative receiver it delivers the same performance. Furthermore, the deterministic complexity and highly parallelizable structure of the proposed detector are well suited for HDL and ASIC implementation. To focus on a specific setting, we consider the indoor MIMO wireless LAN 802.11n standard, taking into account errors in Channel Estimation and a frequency selective, spatially correlated channel model.