PSWF非正弦时域正交调制信号短波信道研究

Research on Time-domain Nonsinusoidal Orthogonal Modulation Signal Based on PSWF in HF Channel

在基于椭圆球面波函数(Prolate Spheroidal Wave Functions,PSWF)的非正弦时域正交调制信号的解调过程中,脉冲正交性对解调性能至关重要。在简要介绍信道模型和非正弦时域正交调制原理的基础上,对信道多径时延、衰减等因素以及调制路数对正交性的影响,进行了理论推导和仿真分析。最后提出:多径时延对正交性的干扰呈规律性起伏变化;非主径信号的强度是影响正交性的主要因素;随着调制路数增加,PSWF脉冲组正交性的恶化程度趋于平稳。

The orthogonality of the PSWF impulses plays an important role,when the nonsinusoidal time-domain orthogonal modulation signal based on PSWF is demodulated.Theoretical analysis and simulation analysis on effects of multipath delay,attenuation and number of modulation channels have been done after the HF Channel model and the principle of nonsinusoidal time-domain orthogonal modulation are introduced.The results show that the effects of multipath delay on orthogonality of the PSWF Impulses change regularly and a cycle is a code time.The attenuation plays a main role in the effects of all factors.The effect of the number of modulation channels tends to be smooth as it increases.