Accurate mutual coupling correction is necessary for an array antenna to reach ultra-low sidelobe level.If the mutual impedance or mutual coupling coefficient matrix of an array isperfectly known,theoretically,one can...Accurate mutual coupling correction is necessary for an array antenna to reach ultra-low sidelobe level.If the mutual impedance or mutual coupling coefficient matrix of an array isperfectly known,theoretically,one can compensate the effects of mutual coupling completelyand realize the desired low sidelobe level.However,the mutual impedance matrix obtainedwhether by calculation or by measurement has limited precision,which limits the effectiveness ofcompensation.This paper deals with the requirements on the precision of mutual impedance forcompensation in ultra-low sidelobe array antennas.The relationship between mutual impedanceerrors and the amplitude and phase errors of an array is derived,by which the relationship betweenthe mutual impedance errors and the sidelobe level is obtained.展开更多
毫米波合成孔径雷达(Ka-SAR)进行俯仰向数字波束形成(digital beam forming,DBF)车载地面验证时,由于车载高程较小使得成像区域地形起伏不可忽略。采用传统扫描接收(scan on receive,SCORE)算法获得的DBF加权系数会存在误差,使合成波束...毫米波合成孔径雷达(Ka-SAR)进行俯仰向数字波束形成(digital beam forming,DBF)车载地面验证时,由于车载高程较小使得成像区域地形起伏不可忽略。采用传统扫描接收(scan on receive,SCORE)算法获得的DBF加权系数会存在误差,使合成波束方向图偏离理想状态,降低系统性能。针对上述问题,本文提出了一种基于多通道SAR的自适应距离向DBF处理算法,对多通道数据进行干涉处理,并通过滤波提取干涉相位,自适应生成加权系数,提高了接收增益。该自适应算法获得的加权系数精度较高,具有处理流程简单、运算量小、便于实时处理的特点。最后,基于仿真和车载实验数据成像,验证了该算法的有效性。展开更多
文摘Accurate mutual coupling correction is necessary for an array antenna to reach ultra-low sidelobe level.If the mutual impedance or mutual coupling coefficient matrix of an array isperfectly known,theoretically,one can compensate the effects of mutual coupling completelyand realize the desired low sidelobe level.However,the mutual impedance matrix obtainedwhether by calculation or by measurement has limited precision,which limits the effectiveness ofcompensation.This paper deals with the requirements on the precision of mutual impedance forcompensation in ultra-low sidelobe array antennas.The relationship between mutual impedanceerrors and the amplitude and phase errors of an array is derived,by which the relationship betweenthe mutual impedance errors and the sidelobe level is obtained.
文摘毫米波合成孔径雷达(Ka-SAR)进行俯仰向数字波束形成(digital beam forming,DBF)车载地面验证时,由于车载高程较小使得成像区域地形起伏不可忽略。采用传统扫描接收(scan on receive,SCORE)算法获得的DBF加权系数会存在误差,使合成波束方向图偏离理想状态,降低系统性能。针对上述问题,本文提出了一种基于多通道SAR的自适应距离向DBF处理算法,对多通道数据进行干涉处理,并通过滤波提取干涉相位,自适应生成加权系数,提高了接收增益。该自适应算法获得的加权系数精度较高,具有处理流程简单、运算量小、便于实时处理的特点。最后,基于仿真和车载实验数据成像,验证了该算法的有效性。