直接检测的全电子THz无线系统中混合PGS设计

Design of hybrid probabilistic and geometric shaping in all-electronic THz wireless system with direct detection

摘要:

太赫兹通信由于具有极大的带宽已成为当前的研究热点，在太赫兹系统中进一步提升系统容量也成为了值得探究的问题。本文利用混合概率和几何整形(PGS)的方案对全电子元件构成的太赫兹系统进行优化，使用成对优化(PO)算法对完成概率整形(PS)后的16阶正交幅度调制(PS-16QAM)的星座点进行位置调整，获得所需的混合概率和几何整形的16阶正交振幅调制(PGS-16QAM)信号。通过测试PS-16QAM、几何整形后的16阶正交幅度调制(GS-16QAM)和PGS-16QAM在不同净速率下对16QAM的优化，验证了混合PGS具有最佳的优化效果。实验证明，当无线传输距离设置为2 m、NGMI阈值设置为0.92时，PGS-16QAM相较于传统的16QAM、PS-16QAM和GS-16QAM，净传输速率分别提升了15.6%、11.8%和3.8%，

Abstract:

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.