临近空间HAPS天地一体化系统具有组网灵活和高效传输的特点，在国防民用、气象预报以及监控等多领域具有广阔的应用，其协作传输模型已作为未来研究的关键技术，且Massive MIMO作为无线通信以及网络的核心技术，其多径信道特征、信号处理以及编码导频设计等领域尚存在大量理论和关键技术有待解决。本项目主要研究临近空间环境的非线性时变信道估计与传输模型、获取其非稳态/非线性时变信道统计特征、开发基于混沌压缩感知的多种信道估计算法，提出精度高以及复杂度低的感知信道算法；以大维随机矩阵理论为基础，挖掘Massive MIMO空间信道维度和频谱资源，建立低复杂度、较小交互信息量的盲导频污染抑制机制和信道算法；搭建仿真系统展开对物理层球面波及多点散射的信道特征研究，以其信道特征及准则为基础，设计Massive MIMO阵列平台。本项目将对关键问题进行系统而深入地研究，取得大量原创性成果达到国内外领先水平。

High altitude platform station (HAPS) near space air-ground integration system has the characteristics of flexible and efficient transmission. It has broad applications in defense, civil weather forecasting and monitoring. Its collaborative transmission model has been the key technology for future research, and Massive MIMO is the core technology of wireless communication and network. There are still a lot of theoretical and key technologies to be solved in the fields of multi-path channel characteristics, signal processing and coding pilot design. This project mainly studies the nonlinear time-varying channel estimation and transmission model in the near space environment, obtains the statistical characteristics of its unsteady/non-linear time-varying channel, develops various channel estimation algorithms based on chaotic compressed sensing, and proposes a high-precision and low-complexity sensing channel algorithm; based on large-dimensional random matrix theory, mining Massive MIMO spatial channel dimensions and spectral resources, establishing blind pilot pollution suppression mechanism and channel algorithm with low complexity and small interactive information; The simulation system is built to study the channel characteristics of the physical layer spherical wave and multi-point scattering. Based on its channel characteristics and criteria, the Massive MIMO array platform is designed. This project will systematically and in-depth study of key issues, and achieved a large number of original results to reach the leading level at home and abroad.