Fig. 1. (a) Structures of the 1D CNN. (b) Convolution principles of the 1D CNN. (c) Structures of the 2D CNN. (d) Convolution principles of the 2D CNN.

Fig. 2. (a) Principle of the iterative pruning FCNN. (b) Principle of the iterative pruning CNN.

Fig. 3. Principle of the Rx DSP.

Fig. 4. Experimental setup of exceeding 200 Gb/s THz wireless transmission over 200 m outdoor 2 × 2 MIMO links at 300 GHz. (a) Block diagram. Photos of the (b) optical transmitter, (c) optical THz conversion module, (d) lens utilized at the receiver, and (e) THz wireless receiver.

Fig. 5. Map of the 200 m THz wireless link.

Fig. 6. Constellation diagrams after decision-directed least mean square (DDLMS) algorithm, 2D CNN, and 2D CNN pruned in X-pol. (a) 0, (b) 6, and (c) 16 dBm.

Fig. 7. BER curves of the 50 GBaud QPSK signals transmitted over a 200 m wireless link at 300 GHz. (a) X-pol. (b) Y-pol.

Fig. 8. Sparsity curves of the 50 GBaud QPSK signals transmitted over a 200 m wireless link at 300 GHz.

Fig. 9. Maximum pruning ratio versus optical power.

Fig. 10. MACC complexity of different equalizers in Y-pol.