A Robust NDA Carrier Tracking Method for LDPC-Coded Systems With Symbol Rate Sampling

In this letter, a robust nondata-aided (NDA) carrier tracking method is proposed for low-density parity-check (LDPC) coded systems with symbol rate sampling. The proposed method has a novel and hybrid carrier tracking loop combined with the frequency-locked loop (FLL), increasing/decreasing sampling rate blocks, phase-locked loop (PLL), and modified symbol decision method, which is capable of improving estimation accuracy of the frequency offsets and phase offsets at low signal-to-noise ratios (SNRs). When applied to the (4096,3072) LDPC coded system, numerical simulations and comparisons are provided to validate the effectiveness of the proposed carrier tracking method in the case of relatively low SNRs.