Improvement on Blind Symbol Rate Detection under Unfavorable Conditions

The performance of the blind symbol rate detection through non-linearity degrades under some conditions, including small excess bandwidth, limited symbol length and low signal-to-noise ratio. The improved algorithm here considers the main disturbance-continuous part of the power spectral of non-linearity as its envelope layer and eliminates it by an envelope sifting process, thus greatly improve the performance of the detectors, especially under one or more unfavorable factors. Simulation results show that the modified method outperforms the original methods in all cases, especially under unfavorable conditions.