A Carrier Acquisition and Tracking Algorithm for High-Dynamic Weak Signal

摘要

This paper studies acquisition and tracking of carriers by the Tracking,Telemetry and Command (TT&C) systems in low Signal-to-Noise Ratio (SNR)and high dynamic conditions for deep space applications.An associated carrier acquisition and tracking algorithm is proposed and it features FFT frequency-domain shift and accumulation algorithm in combination with variable bandwidth FLL-PLL algorithm with Doppler rate pre-compensation.The algorithm not only captures signal with high dynamics and low SNR but also achieves high tracking accuracy.Simulation results show that the proposed associated frequency esti-mation algorithm is capable of carrier frequency estimation with an error less than 0.5 Hz and it tolerates high Doppler dynamics under Ebo as low as 3 dB.