Fig. 1. Stokes spatial multiplexing transmitter structures. (a) Traditional structure; (b) phase optimization based structure

Fig. 2. Structures of Stokes receiver

Fig. 3. Results of spectral compression obtained using steepest descent method. (a) Leakage power ratio varies with compression ratio; (b) average power spectral density at compression ratio of 1/4; constellation diagrams of signal (c) before and (d) after compression

Fig. 4. Diagram of phase optimization algorithm. Dotted arrow represents shifting direction of register

Fig. 5. Stokes spatial multiplexing spectrum compression results