Reconfigurable MIMO Detector Design And Implementation In Broadband Wireless Communication Systems

At present, the high-speed broadband wireless MAN technology IEEE802.16 (WiMAX), 3GPP long term evolution (LTE) technology and 3GPP2 Ultra Mobile Broadband (UMB) technology, use MIMO technology to increase channel capacity and enhance the spectrum utilization. However, MIMO detecting, separating the mixed-signals through MIMO channel, is one of the key techniques of MIMO system.The classic detection algorithms,include the linear detection algorithm, the interference cancellation detection algorithm , the improved detection algorithm and the spherical decoding algorithm. QRM-MLD-ASESS algorithm belongs to the multi-choice interference cancellation algorithms, which can balance the performance and complexity, with high performance close to the ML algorithm, low complexity close to linear detection algorithm, with great flexibility.This essay mainly focuses on the multi-choice interference cancellation detection techniques in MIMO systems. This essay introduced a variety of MIMO detection algorithms, and simulated their performance, then descripbed in detail reconfigurable MIMO detector hardware design and implementation in broadband wireless communication systems,and propose simplified optimization program based on hardware.At first this essay introduced the next-generation broadband wireless communication systems, like WIMAX, LTE, UMB system, and the main MIMO techniques’application in these systems.Then the classical MIMO system architecture, V-BLAST systems are introduced. The principles of some classic MIMO detection algorithms, which include Maximum Likelihood, Sphere Decoding, Zero Forcing, Minimum Mean Square Error and Interference Cancellation, are demonstrated. Then the simulation results of these algorithms are compared and analyzed.After that, the MLD, QRM-MLD and QRM-MLD-ASESS algorithm are introduced in detail, and the complexity of three algorithms and the MMSE algorithm are compared. QRM-MLD-ASESS algorithm is a kind algorithm with good performance and moderate complexity. Then the reasons of implementing by FPGA are analysed and the basic structure of the algorithm was proposed.Finally, reconfigurable MIMO detector based on QRM-MLD-ASESS algorithm was introduced, data interfaces format were defined, the algorithm process was described in detail, function diagrams were given. The fixed-point performance simulation was offered, the fixed-point definition close to the performance of float point was selected. Simplified FPGA proposals of each module were offered by the characteristics of each one, hardware resources are decrease through the iterative optimization, and the list of hardware resource consumption was given. Not only the performance and resource requirements were met, and reconfigurable functions were supported.At the end of this essay, some technique points to be researched in the future are summarized.