Constellation basis decomposition based blind equalization processing of four-dimensional modulation

Blind equalization processing of four-dimensional (4D) signal is a key factor to 4D modulation based system, in order to solve this problem, we propose "constellation basis'' decomposition based blind equalization processing scheme for (4D) modulation format. A 4D modulation based optical OFDM system is simulated to verify the performance of "constellation basis'' decomposition scheme. Compared to the data aided equalization with least mean square algorithm, the proposed scheme shows a better performance in the case of 4D modulation format. And it is also demonstrated that the proposed scheme can simultaneously realize blind equalization compensation for system or channel impairments including chromatic dispersion, phase noise, I/Q imbalance, etc. Meanwhile, it allows for flexible spectrum efficiency transmission.