In this letter, we address the problem of estimating the integer part of carrier frequency offset (CFO) in space frequency block codes (SFBCs) systems with orthogonal frequency division multiplexing (OFDM) modulation schemes. We derive a maximum-likelihood (ML) estimator assuming that the receiver has two receive antenna, and then we extend the analytical analysis to an arbitrary number of receive antennas. The proposed estimator is designed in a way that exploits the additional two-dimensional space-frequency redundancy provided by SFBCs. Because of its popularity, Alamouti code is chosen to be the code of interest. However, a similar analytical treatment could be applied to any other code. The computational complexity analysis and Monte Carlo experiments are carried out to verify effectiveness of the proposed estimator for practical applications.

中文翻译：

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Alamouti SFBC-OFDM 系统的最大似然整数频率偏移估计器

在这封信中，我们解决了在具有正交频分复用 (OFDM) 调制方案的空间频率块码 (SFBC) 系统中估计载波频率偏移 (CFO) 整数部分的问题。我们推导出最大似然 (ML) 估计量，假设接收器有两个接收天线，然后我们将解析分析扩展到任意数量的接收天线。所提出的估计器的设计方式利用了 SFBC 提供的额外二维空间频率冗余。由于其受欢迎程度，Alamouti 代码被选为感兴趣的代码。但是，类似的分析处理可以应用于任何其他代码。进行了计算复杂性分析和蒙特卡罗实验，以验证所提出的估计器在实际应用中的有效性。