一种在全数字锁相环中进行振荡器增益估计的新算法

A Novel Algorithm to Evaluate the Gain of DCO in ADPLL

提出一种在全数字锁相环中对数控振荡器进行增益估计的新算法。此算法充分利用全数字锁相环内部的数字信息,通过计算相位误差、频率误差和振荡器的频率控制字的变化,对数控振荡器的增益进行实时估计,使全数字锁相环对外界环境变化的免疫程度更高。此算法适用于所有采用基于累加器结构的全数字锁相环,而且可以在应用最广泛的二阶Ⅱ型锁相环中准确地工作。

A novel algorithm of evaluating the gain of DCO in all digital PLL （ADPLL） is proposed. It utilizes the digital information in ADPLL and evaluates the gain of DCO by calculating the variation of phase error, frequency error and the oscillator tuning word. As a result, the ADPLL is more immune to the environment. This algorithm is suitable for all counter-assistant ADPLLs, and it can work well in the type-II, 2rd order ADPLL, which is widely used in wireless communications.