一种基于频偏函数最优解估计的VCO非线性校正方法

Chirp信号产生是Chirp-UWB系统首先要解决的问题,基于VCO产生的Chirp信号线性度不够高,影响系统的分辨率和处理增益,因此,需要对VCO进行非线性校正。文章通过分析VCO非线性校正原理,提出了一种基于频偏函数最优解估计的非线性校正方法。该方法首先利用每个信号周期内的频率信息估计频偏函数,然后利用频偏函数对VCO进行非线性校正。仿真结果表明,该方法可以使VCO输出信号的线性度得到提高。

VCO Nonlinearity Correction Method Based on Optimal Solution Estimation of Frequency Offset Function

Generation of Chirp signal is the primary problem in Chirp-UWB system.The common method is using VCO to generate Chirp signal,but the linearity is not so high that the accuracy and processing gain of the system is affected.This paper analyzes the principle of VCO nonlinearity correction and proposes one nonlinearity correction method based on optimal solution estimation of frequency offset function.The method estimates frequency offset function using frequency in every period of the signal and then corrects the nonlineartiy of VCO.Simulation results show that the proposed method improves the linearity.