频偏估计是MIMO—OFDM系统设计的一个关键问题。本文在前人研究成果的基础上,提出了一种基于OFDM系统固有虚子载波结构的低复杂度载波频偏估计算法,不需要任何额外的导频(零或非零)资源,在小频偏范围内可以精确估计出频偏,在频偏范围较大时,可通过增加泰勒级数近似项和应用迭代机制继续获得很高的估计精度。
Carrier frequency offset (CFO) estimation is a key problem for MIMO-OFDM system. In this paper,a low-complexity blind CFO estimation algorithm with virtual subcarriers has been proposed. Since virtual subcarriers are intrinsic for OFDM signals,the algorithm needs no pilots (zero or nonzero) at all. In small estimation range, accurate estimation can be got;in larger range, by exploiting more terms of Taylor' s series approximation and iterative technique,the algorithm can also get fine result.