Initial synchronization for 3GPP NTN system under a large of Doppler offset

This paper presents a robust Primary Synchronization Signal (PSS) detector design for 5G New Radio (NR) non-terrestrial networks (NTN), addressing the challenges imposed by large Doppler shifts due to Low Earth Orbit (LEO) satellite motion. While the 3GPP terrestrial network (TN) specifications limit the initial Carrier Frequency Offset (CFO) error that user equipment (UE) demodulators must compensate to 5 parts per million (ppm), NTN systems require compensation of up to approximately 24 ppm. To enable reliable operation under low Signal-to-Noise Ratio (SNR) conditions in NTN, a cross-correlation-based detection approach with integrated CFO estimation is proposed. Simulation results demonstrate that the proposed design maintains robust detection performance under significant Doppler shifts in low SNR environments.