A study on performance improvement of IMDD-UFMC with modified K-means non-uniform quantization

Abstract In this paper, a modified K-means-based low complexity the nonuniform quantization scheme is proposed in the intensity-modulated direct detection universal filter multicarrier (IMDD-UFMC) system to improve system performance. Owing to the good cluster property of our scheme, the optimal quantization levels can be directly figured out, and the complexity induced by the probability density function (PDF) estimation can be reduced. By utilizing this scheme, the low quantization noise and peak-to-average power ratio (PAPR) can be achieved by assigning finer quantization steps for the low-level area signals. And, to manifest this scheme, the IMDD-UFMC-based numerical simulation and experimental platform with 10-Gb/s 16-QAM signal over 20 km fiber are constructed. The corresponding results show that our method always achieves the better performance, measuring in the form with the error-vector-magnitudes and bit error rate, compared to the common uniform quantization scheme even with the low-bit resolution case.