Design of hybrid probabilistic and geometric shaping in all-electronic THz wireless system with direct detection
Terahertz communication has become a current research hotspot due to its extremely large bandwidth,and further improving the system capacity in terahertz systems has also become a problem worth exploring.This paper optimizes the terahertz system composed of all-electronic components using a hybrid Probability and Geometric Shaping(PGS)scheme.The Pairwise Optimization(PO)algorithm is employed to adjust the Probabilistically Shaped 16-ary Quadrature Amplitude Modulation(PS-16QAM)signal after probabilistic shaping to obtain the desired hybrid PGS-16QAM signal.By testing the optimization effects of PS-16QAM,Geometric Shaping(GS)-16QAM and PGS-16QAM on uniform 16QAM at different net rates,it is verified that the hybrid shaping has the best optimization effect.When the wireless transmission distance is set to 2 meters and the Normalized Generalized Mutual Information(NGMI)experimets have shown that threshold is set to 0.92,PGS-16QAM achieves a net transmission rate increase of 15.6%,11.8%,and 3.8%compared to traditional 16QAM,PS-16QAM,and GS-16QAM,respectively.
terahertzProbabilistic Shaping(PS)Geometric Shaping(GS)Pairwise Optimizationhybrid Probability and Geometric Shaping(PGS)Normalized Generalized Mutual Information(NGMI)