电离层和海态对天波雷达多普勒谱的影响

在Walsh海杂波模型的基础上，结合实测天波超视距雷达(over the horizon radar, OTHR)回波数据，同时考虑海面洋流、电离层垂直运动以及电离层非平稳性引起的相位污染的影响，提出了改进的OTHR海杂波模型。利用改进模型，从OTHR检测舰船速度盲区的角度深入分析了海态和电离层非平稳性对OTHR多普勒谱的影响。仿真数据和实测数据的对比说明了改进模型能够较好的模拟实测海杂波，得出的结论为选择最佳的OTHR工作参数和电离层传播信道提供了理论参考。 

Effect of Ionosphere and Oceanic State on Doppler Spectrum of Over the Horizon Radar

On the basis of the Walsh sea clutter model and measured data of over the horizon radar(OTHR), a modified OTHR sea clutter model is proposed. Ocean current, vertical motion of the ionospere and the phase contamination which caused by nonstationarity of the ionospere are all considered in this proposed model. Using the modified sea clutter model, the effects derived from oceanic state and nonstationarity of the ionospere are deep analyzed based on blind zone on Doppler spectrum of ships. After comparing with the real sea clutter data, it shows that the modified OTHR sea clutter model is better than original Walsh model. The results will provide theoretical references for the optimal OTHR parameters and ionospheric channel selection.