Decision directed versus non-data aided plls: A comparative review
Decision directed versus non-data aided plls: A comparative review
复制标题
DOI：
10.1109/tcomm.2010.04.080286
复制
发表时间：
2010-04
影响因子：
8.3
通讯作者：
Shay Landis;B. Bobrovsky
中科院分区：
文献类型：
--
作者：
Shay Landis;B. Bobrovsky
在热噪声和1/f2相位噪声的干扰下，研究了离散时间判决引导（DD）和非数据辅助（NDA）一阶锁相环（PLL）对QPSK调制信号的性能。一个著名的连续时间模型，提出了密切接近循环的行为。使用连续时间模型，福克-普朗克技术被应用于计算两个PLL的平均失锁时间（MTLL）。我们使用MTLL作为优化准则来优化环路滤波器。在最优MTLL的基础上，我们确定了一个PLL优于另一个PLL的区域。给出了蒙特-卡罗仿真结果来验证解析分析。对于所研究的设置，无论相位噪声电平如何，当SNR低于4.5dB时，NDA PLL的性能优于DD PLL。二阶锁相环的结果的适用性进行了讨论。
The performance of discrete-time Decision Directed (DD) and Non-Data Aided (NDA) first-order Phase Looked Loops (PLL) for a QPSK modulated signal is evaluated under the disturbance of thermal noise and 1/f2 phase noise. A well known continuous-time model is presented that closely approximates the loop¿s behavior. Using the continuous time model, Fokker-Planck techniques are applied to compute the Mean Time to Lose Lock (MTLL) for both PLLs. We optimize the loop filter using the MTLL as the optimization criterion. On the basis of the optimal MTLL, we determine the regions where one PLL outperforms the other. Monte-Carlo simulation results are presented to validate the analytic analysis. For the setting under study, the NDA PLL outperforms the DD PLL for SNR below 4.5dB regardless of the phase noise level. Applicability of the results for a second-order PLL is discussed.