高频电离层信道4F4T4PSK系统性能

本文提出了高频电离层信道４Ｆ４Ｔ４ＰＳＫ通信系统性能分析方法，给出了其误码率表达式。４Ｆ４Ｔ４ＰＳＫ系统在时变信道上传输出为加性噪声和多条具有不同时延，不同频移和不同到达角传播路径信号的总和。误码率表达式考虑了信道中存在的瑞利衰落，频率与时间选择性衰落，四重频率分集及白噪声的影响。给出了该“不可克服误码率”与信道中存在的归一化最大多径时延和归一化多普勒散布的关系曲线，并根据其结果，讨论了该本制对多

Performance for 4F4T4PSK Communication System on HF Ionospheric Channels

This paper presents a method for determining the error probability of 4F4T4PSK communication system on HF ionospheric channels. The signals of 4F4T4PSK system are transmitted in the time-varying channels, and the output of the channels includes additive white noise and the sum of singals on several paths with different time delays, frequency shifts and arrival angles. In error-rate expression the effects of Rayleigh fading, frequency-and time-selective fading on HF ionospheric channels, quadruple frequency diversity and white noise have been considered. The irreducible error probability Pe() of 4F4T4PSK system is plotted as a function of the maxium normalized differential time delay and normalized doppler spreads. Finally, using Sunde's method, the error rate of 2DPSK system on HF ionospheric channels are studied and compared with Gaarder's method.