Generation of (3, 1) Vector Signal Based on Probabilistic Shaping Technology without Precoding

Figure 3

Schematic diagram of PS (3, 1) photonic vector signal generation: (a) the method of generating PS (3, 1) electronic vector signals; (b) relationship between MZM output power and DC bias voltage; (c) optical spectrum of the signal at the MZM output; (d) distribution of pre-PD constellation points; (e) distribution of post-PD constellation points.