电子学报2011，Vol.39Issue(1)：1-6,6.
低信噪比下锁频锁相器性能分析及改进
Performance Analysis and Improvement of Phase and Frequency Detector at Low SNR
摘要
Abstract
Under the condition of low Signal to Noise Ratio ( SNR) andlarge frequency offset, the impact mechanism of window type on acquisition time,frequency range,noise threshold and phase jitter in Phase and Frequency Detector (PFD) is presented by theoretic analysis and simulations. Closed-form expression of equivalent noise Power Specmran Density (PSD) is derived.The results show that the bigger window has a lower noise threshold and less phase jitter, but acquisition rate is slower. Modified algorithm replaces the phase detector output with its polarity. The new algorithm not only improves the performance of acquisition time and the phase jitter by increasing the gain of phase detector and reducing equivalent noise Power Spectrun Density respectively, but also reduces hardware implementation complexity. In last, the new algorithm is verified by simulations.关键词
锁频锁相器/科斯塔斯环/载波恢复/低信噪比Key words
phase and frequency detector/Costas loop/carrier recovery/low signal to noise ratio分类
信息技术与安全科学引用本文复制引用
晏辉,张忠培..低信噪比下锁频锁相器性能分析及改进[J].电子学报,2011,39(1):1-6,6.基金项目
国家863高技术研究发展计划(No.2009AA01Z234) （No.2009AA01Z234）
