Turbo Nonlinear Equalization for Millimeter-Wave Communications Systems

• Main Authors: Cheng-Ting Tsai, 蔡承廷
• Other Authors: Fang-Biau Ueng
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/92727980874374213081

碩士 === 國立中興大學 === 通訊工程研究所 === 105 === In the thesis, for the 5G millimeter-wave communications, which operating in extremely high frequency and have enormous bandwidth. It must use RF power amplifier which cause nonlinear distortion may pose great challenges to signal detections. Compare to classical schemes, which calibrate nonlinear distortions in transmitters, the thesis suggest a nonlinear equalization algorithm and combine turbo code to enhance reliability, with which the multipath channel and unknown symbols contaminated by nonlinear distortions and multipath interferences are estimated in receiver-ends. Attributed to the nonlinearity and marginal integration, the related posterior density is analytically hard and most existing linear equalization schemes may become invalid. To solve this problem, the Monte-Carlo sequential importance sampling based particle filtering is used, and the non-analytical distribution is approximated numerically by the evolving probability-mass. By applying the Taylor’s expansion, a local-linearization observation model is further constructed to facilitate the practical design of a sequential detector. Thus, the unknown symbols are detected recursively as new observations arrive. Simulation results validate the proposed joint detection scheme. By excluding transmitting pre-distortion of high complexity, the presented algorithm is specially designed for the receiver-end, which provides a promising framework to millimeter-wave communications.