说明：  本篇论文研究的 FDD 模式下的 Massive MIMO OFDM 系统的信道估计方法，通过分析 MIMO OFDM 系统存在的空时共同稀疏性，应用结构化理论处理 Massive MIMO 信道。为了 减少导频的消耗，提出适合的估计方法
(In this paper, the channel estimation method of Massive MIMO OFDM system in FDD mode is studied Space-time common sparsity in MIMO OFDM system is applied to deal with Massive MIMO channel.In order to Reduce the pilot frequency consumption and put forward a suitable estimation method)