WANG Xu-dong, FAN Tao, HUANG Qiang-hui, et al. SOQPSK Carrier Tracking Technology with Large Doppler Frequency Offset Based on FFT Guided Costas Loop[J]. Acta Electronica Sinica, 2016, 44(2): 491-496.
WANG Xu-dong, FAN Tao, HUANG Qiang-hui, et al. SOQPSK Carrier Tracking Technology with Large Doppler Frequency Offset Based on FFT Guided Costas Loop[J]. Acta Electronica Sinica, 2016, 44(2): 491-496. DOI: 10.3969/j.issn.0372-2112.2016.02.034.
SOQPSK signal has constant envelope and continuous phase
and has high power and spectral efficiency.It will have broad application prospects in satellite communications
deep space communications and aeronautical telemetry systems.To ensure SOQPSK carrier signal can be applied to larger Doppler offset system
this paper presents a SOQPSK signal carrier tracking technology which uses FFT guide COSTAS loop.First
a rough estimate by FFT of the Doppler frequency makes carrier frequency offset be limited to a small range
and then uses the improved COSTAS loop to track carrier residuals and phase error
thus achieving a steady carrier track for SOQPSK signal with large carrier frequency offset.Simulation results show that the proposed algorithm not only is able to track large carrier frequency offset
but also is better to track small frequency offsets than traditional methods.