基于对称帧结构的联合频相估计

针对短突发通信系统中联合频相估计的剩余频偏对相偏估计的影响，首次引入对称帧结构的概念.首先，基于一种通用（非对称）帧结构，给出了对称帧结构的概念，并推导出基于此结构的数据辅助和非数据辅助两种同步模式下的载波参数估计克拉美罗界.然后，根据该对称帧结构下载波参数估计克拉美罗界的特征，提出了一种基于对称帧结构的联合频相估计.仿真结果表明，以基于最大似然准则的联合频相估计为例，相较于采用非对称帧结构的相偏估计，采用对称帧结构的相偏估计可以获得更低的均方误差和更大的抗频偏能力.

Joint Frequency-Phase Offset Estimation Based on a Symmetrical Frame Structure

Considering the impact of the joint frequency-phase offset estimation frequency error on the phase offset estimation in short burst communication systems,a symmetrical frame structure is introduced.First,based on a generalized (asymmetrical) frame structure we give a concept of the symmetrical frame structure and then develop the corresponding data-aided (DA) and non-data-aided (NDA) Cramer-Rao Bounds (CRBs) for the carrier parameter estimation.Then,according to the above CRB characteristic a joint frequency-phase offset estimation is proposed using the symmetrical frame structure.Taking the maximum likelihood (ML) based joint frequency-phase offset estimation for an example,simulation results show that the phase offset estimation based on the symmetrical frame structure can achieve lower mean square error (MSE) and have better ability against the large frequency offset compared with the phase offset estimation based on the asymmetrical frame structure.