联合频相估计中的对称化解耦合技术

在突发通信系统中，针对联合频相估计中剩余频偏严重影响相偏估计的缺陷，提出了一种对称化解耦合技术．首先，分析了对称化的采样时刻集可以使联合频相估计解耦合的特点，并由此提出了对称化解耦合技术; 然后，在数据辅助和非数据辅助两种同步模式下，将该技术运用在联合频相估计中，并给出了相应的理论分析; 最后，提出了串行/并行联合频相估计器的概念．理论分析和仿真结果表明，经过对称化解耦合操作可以降低相偏估计的均方误差，同时也具有更强的对抗剩余频偏的能力，可容忍的剩余频偏范围至少扩大为原来的三倍．另外，该技术对具体的联合频相估计算法没有要求，具有一定的普适性．

Symmetry decoupling technique in joint frequency-phase estimation

In burst-mode communication systems, considering the great influence of the residual frequency offset on the phase estimation in joint frequency-phase estimation, the symmetry decoupling technique is proposed. First, the characteristic is analyzed that the symmetrical set of sampling instants can decouple the joint frequency-phase estimation. Then the concept of symmetry decoupling technique is proposed. Second, the symmetry decoupling technique is applied to the joint frequency-phase estimation under both the data-aided mode and non-data-aided mode. Also, the relative theoretical analysis is given. On this basis, the concepts of serial/parallel joint frequency-phase estimators are proposed. Theoretical analysis and simulation results show that the structure processed by the symmetry decoupling technique can achieve a lower mean square error and improve the ability to tolerate the residual frequency offset by three times at least. Besides, the proposed technique has universality which can be applied to other joint frequency-phase estimation algorithms.