针对突发通信中定时同步问题,提出了一种基于最小化星座点离散度(MCD)的MPSK定时盲同步方法。该方法结合模式识别理论的概念,定义了MPSK的星座点离散度作为代价函数,并设计了基于该代价函数的近似线性的定时偏差分量提取函数(TED)。最后采用插值技术,通过迭代MCD来达到定时同步。该方法不需要训练序列,不受固定载波相位偏移的影响,仿真表明该方法可使MPSK快速达到定时同步状态。
A new multiple phase shift keying (MPSK) timing blind recovery method based on minimum constellation dispersion (MCD) is presented to solve the timing synchronization problem in burst communications. By associating with the pattern recognition theory, the constellation dispersion of MPSK is defined as the cost function and a new approximately linear time error detector (TED) function based on this cost function is proposed. The timing synchronization is achieved by iter- ating MCD and the interpolating technology without the aid of training sequences. The results from the simulation show that the method can quickly achieve timing synchronization in MPSK demodulation and avoid the effect of carrier phase offset.