Fig. 1. Schematic of MIMO nonlinear self-interference optical domain cancellation system assisted by LS algorithm

Fig. 2. Illustration of crosstalk and nonlinearity in the case of two transmitting antennas

Fig. 3. Tap coefficients when the crosstalk coefficient is 0.1. (a) Directly computed tap coefficients; (b) tap coefficients obtained by taking absolute values and normalizing

Fig. 4. The order of the LS algorithm used for parameter estimation of each basis function and the runtime of the LS algorithm, under different threshold settings when the crosstalk coefficient is 0.1

Fig. 5. EVM of the signal of interest and SIC depth after analog SIC and further digital SIC when the crosstalk coefficient is 0.1

Fig. 6. Electrical spectra and constellation diagrams without SIC, with analog SIC, and with analog and digital SIC when the crosstalk coefficient is 0.1. (a) Threshold is set to 0; (b) threshold is set to 0.06; (a) threshold is set to 0.2

Fig. 7. Order of LS algorithm used for parameter estimation of each basis function and running time of LS algorithm, under different threshold settings when the crosstalk coefficient is 0.3

Fig. 8. EVM of the signal of interest and SIC depth after analog SIC when the crosstalk coefficient is 0.3