The Research Of Key Technologies In3D MIMO

MIMO antenna technology has a great advantage for supporting high data transmission, improving the spectrum utilization and improving the power efficiency. It has been widely used in LTE,802.11n (WLAN) and HSPA system. However, now the MIMO antenna technology research is largely confined to the one-dimensional antenna array system, i.e the level of the base station antenna beam surface, and the research of beamforming technology, channel modeling and channel estimation technology is based on the one-dimensional linear array antenna system. As large-scale antenna research more and more widely, for further utilization of space, increasing the coverage and controlling inter-cells interference, the research of extending the antenna layout to the vertical dimension, the vertical beaming and the use of array antenna has attracted more and more studies. The mature of Antenna manufacturing technology such as AAS (antenna array system), prompts the implementation of this research is possible. It is significative to study3D channel modeling, beamforming, user selection and channel estimation technology for Appling to array antenna.In this paper, The realization of the3D channel modeling is based on the research of2D MIMO channel modeling i.e. SCM, SCME and IMT-A, combining with the parameters provided by WINNER and related papers, extending the channel to3D space, which more accurately describing the characteristics of the real channel space. Array antenna is the base of the realization of the3D multi-input multi-output (MIMO) system, in this paper. The simulation is carried out to the system throughput under the different configuration for the array antenna. A growing number of antenna array brought greater spatial degrees of freedom, but also brought greater complexity and overhead for the beaming algorithm, user selection algorithm and channel estimation and feedback. Based on the correlation between the vertical plane array antenna element, A optimization algorithm which suitable for the array antenna is proposed in this paper, i.e. optimized Zero-Forcing beamring algorithm and the SUS user selection, the performance of the two algorithms and complexity are simulated and analyzed in this paper.From the simulation we find that with the same array element number, by adjusting the antenna layout and antenna spacing, array antenna can obtain higher throughput than linear array antenna. But the array antenna is suitable for the large-scale MIMO scenario, compared with the linear array antenna which can improve space utilization. We also found that the smaller of the antenna spacing, the closer the performance of the optimized Zero-Forcing beamring algorithm with the algorithm that using all channel response of antenna elements. And it is also discovered with the increase of antenna spacing, the algorithm performance is also reduced. As to the optimized SUS algorithm, it can reduce the computation complexity effectively to50%witho reducing the performance25%compared with the no optimized SUS algorithm.