The cyclotron autoresonace masers with a large-orbit electron ring in a dielectric-loaded waveguide have been analyzed.The stability properties are investigated self-consistentlyon the basis of the linearized Vlasov-M...The cyclotron autoresonace masers with a large-orbit electron ring in a dielectric-loaded waveguide have been analyzed.The stability properties are investigated self-consistentlyon the basis of the linearized Vlasov-Maxwell equations.The numerical results show that thedielectric liner can greatly reduce the energy of the electron beam,and a novel effective radiationdevice with low electron beam energy in the millimeter and submillimeter wave region have beenproposed.展开更多
为了实现天问一号高分辨率相机在大椭圆轨道下对火星表面高质量成像,建立了基于火星的大椭圆轨道像移计算模型。对大椭圆轨道和像移计算方法进行研究。首先,根据大椭圆轨道的特点,分析大椭圆轨道与近圆轨道存在的差别。接着,依据椭圆特...为了实现天问一号高分辨率相机在大椭圆轨道下对火星表面高质量成像,建立了基于火星的大椭圆轨道像移计算模型。对大椭圆轨道和像移计算方法进行研究。首先,根据大椭圆轨道的特点,分析大椭圆轨道与近圆轨道存在的差别。接着,依据椭圆特性和角动量守恒原理计算高分辨率相机到火星中心的距离、椭圆运动轨道速度、轨道速度与离心速度的夹角。然后,根据齐次坐标变换的方法将火星景点坐标系与高分辨率相机坐标系建立联系,通过对位置关系的求导得出像移速度。最后,通过动态成像试验验证了像移补偿计算方法的正确性和对图像质量的影响。实验结果表明:大椭圆轨道像移补偿计算方法正确;动态传函大于0.1,满足动态传函不小于0.1的指标要求;像移匹配(Modulation transfer function,MTF)最小值为0.953,满足不低于0.95的指标要求。展开更多
文摘The cyclotron autoresonace masers with a large-orbit electron ring in a dielectric-loaded waveguide have been analyzed.The stability properties are investigated self-consistentlyon the basis of the linearized Vlasov-Maxwell equations.The numerical results show that thedielectric liner can greatly reduce the energy of the electron beam,and a novel effective radiationdevice with low electron beam energy in the millimeter and submillimeter wave region have beenproposed.
文摘为了实现天问一号高分辨率相机在大椭圆轨道下对火星表面高质量成像,建立了基于火星的大椭圆轨道像移计算模型。对大椭圆轨道和像移计算方法进行研究。首先,根据大椭圆轨道的特点,分析大椭圆轨道与近圆轨道存在的差别。接着,依据椭圆特性和角动量守恒原理计算高分辨率相机到火星中心的距离、椭圆运动轨道速度、轨道速度与离心速度的夹角。然后,根据齐次坐标变换的方法将火星景点坐标系与高分辨率相机坐标系建立联系,通过对位置关系的求导得出像移速度。最后,通过动态成像试验验证了像移补偿计算方法的正确性和对图像质量的影响。实验结果表明:大椭圆轨道像移补偿计算方法正确;动态传函大于0.1,满足动态传函不小于0.1的指标要求;像移匹配(Modulation transfer function,MTF)最小值为0.953,满足不低于0.95的指标要求。
