Phased array (PA) radar is one of the most popular types of radar. In contrast to PA, the frequency diverse array (FDA) is a potential solution to suppress range-related interference because of its time-range-angle-de...Phased array (PA) radar is one of the most popular types of radar. In contrast to PA, the frequency diverse array (FDA) is a potential solution to suppress range-related interference because of its time-range-angle-dependent beampattern. However, the range-angle coupling inherent in the FDA transmit beampattern may degrade the output signal-to-interference-plus-noise ratio (SINR). We propose a dot-shaped beamforming method based on the analyzed four subarray-based FDAs and subarray-based planar FDAs using a sinusoidally increasing frequency offset with elements transmitting at multiple frequencies. The numerical results show that the proposed approach outperforms the existing log-FDA with logarithmical frequency offset in transmit energy focus, sidelobe suppression, and array resolution. Comparative simulation results validate the effectiveness of the proposed method.展开更多
频率分集阵列(Frequency Diverse Array, FDA)是作为一种全新的电扫描雷达体制,其方向图所具有的时间-距离-角度三维相关特性在电子对抗和安全通信等领域有广阔的应用前景。一维均匀线性FDA阵列(Uniform Linear Array Frequency Diverse...频率分集阵列(Frequency Diverse Array, FDA)是作为一种全新的电扫描雷达体制,其方向图所具有的时间-距离-角度三维相关特性在电子对抗和安全通信等领域有广阔的应用前景。一维均匀线性FDA阵列(Uniform Linear Array Frequency Diverse Array, ULFDA)的发射方向图存在角度-距离耦合问题,针对这一问题,在对称子阵密度锥削阵结构的基础上,通过正弦频控函数取代原有的均匀线性函数,得到了FDA的点状波束指向控制方法。此外,针对FDA方向图的时变问题,得到了基于子阵结构的密度锥削阵sin-FDA主波束在角度维指向固定、距离维变化时的结论。展开更多
针对雷达电子战中,敌方无源探测雷达通过接收干扰机信号实现测向定位,威胁我方干扰机安全的问题,提出一种基于频率分集阵列(Frequency Diverse Array,FDA)的测向交叉定位欺骗技术。首先在建立FDA阵列模型的基础上,通过欧拉公式得到采用...针对雷达电子战中,敌方无源探测雷达通过接收干扰机信号实现测向定位,威胁我方干扰机安全的问题,提出一种基于频率分集阵列(Frequency Diverse Array,FDA)的测向交叉定位欺骗技术。首先在建立FDA阵列模型的基础上,通过欧拉公式得到采用非线性频控函数的FDA阵列因子及相位方向图;然后推导了FDA阵列作用于干涉仪测得的信号到达角β、虚拟发射机在X轴的坐标位置x;接着,以干涉仪测向欺骗为基础,分析了FDA干扰机对测向交叉定位系统的欺骗原理及定位精度。仿真结果表明:通过合理地对载频、阵元数目、频偏的选择可以较好地实现在远场条件下FDA阵列对干涉仪测向的欺骗效果;在合理选择其他参数的同时,测向精度越高、定位模糊区面积越小,且定位虚拟干扰机位置始终落在50%CEP半径之外。展开更多
频率分集阵列(Frequency Diverse Array,简称FDA)在埋体管线的探测识别与成像中具有很大优势,利用其灵活的波束控制和信号处理性能,能够摆脱传统阵列发射信号限制,灵活接收和处理复杂信号。通过发出窄带信号进而获得宽带信号探测参数,...频率分集阵列(Frequency Diverse Array,简称FDA)在埋体管线的探测识别与成像中具有很大优势,利用其灵活的波束控制和信号处理性能,能够摆脱传统阵列发射信号限制,灵活接收和处理复杂信号。通过发出窄带信号进而获得宽带信号探测参数,大大降低操作成本,实现高效率、高精度、高性价比三维立体成像。现如今埋体管线探测成为城市发展中不可避免的痛点,小埋藏体检测成像更是难点问题。文章提出一种基于多进多出技术(Multiple-Input Multiple-Output,简称MIMO)的频率分集阵列三维合成孔径雷达(3D-FDA-MAR)成像方法,并将MIMO阵列引入频率分集阵列实现三维成像,建立了MIMO-FDA三维形貌成像模型。该多进多出频率分集阵列在三维空间中能够随平台运动而运动,在沿航向处得到综合孔径,根据切航向阵列能够获得仿真频率分集阵列平面,从而得到目标物成像的三维立体效果,实现精准定位,全空间透视探测,智能3D成像,小埋藏体的精准检测诊断。展开更多
共形频控多输入多输出(Frequency diverse array multiple input and multiple output,FDA-MIMO)系统的波束图由俯仰角、方位角、距离三维信息控制,能够进一步提高系统的自由度。随着人们对高分辨目标探测性能以及高空气动力学性能的需...共形频控多输入多输出(Frequency diverse array multiple input and multiple output,FDA-MIMO)系统的波束图由俯仰角、方位角、距离三维信息控制,能够进一步提高系统的自由度。随着人们对高分辨目标探测性能以及高空气动力学性能的需求增加,研究共形FDA-MIMO阵列波束图综合方法很有意义。本文详细推导了共形FDAMIMO系统的信号建模和波束图分析的数学过程,并提出一种基于参数迭代的发射接收联合权向量优化算法以得到高分辨率的波束图。该算法首先建立一个二阶锥规划(Second-order cone programming,SOCP)模型,并利用交替方向乘子法(Alternating direction method of multipliers,ADMM)实现参数分离,原问题分为两个子问题。最后分别对各个子问题进行优化。数值仿真表明所提算法相比于传统算法性能更有优势,同时其收敛性得到验证。此外,为进一步分析系统特性,本文讨论了不同系统参数,如发射阵列阵元数、接收阵列阵元数、频控阵频偏大小以及不同频偏方式对本文所提算法下的波束图影响。展开更多
The seriously range-ambiguous clutter is one of the main problems in clutter suppression for hypersonic vehicle-borne forward-looking radar. An approach based on the frequency diverse array (FDA) technique is proposed...The seriously range-ambiguous clutter is one of the main problems in clutter suppression for hypersonic vehicle-borne forward-looking radar. An approach based on the frequency diverse array (FDA) technique is proposed to mitigate the range ambiguous clutter. The frequency increment is designed to distinguish the clutter at ambiguous ranges and suppress the clutter by using a subspace projection algorithm. On the platform with high altitude or limited array antennas, the proposed method performs better for its independence of the elevation degrees-of-freedom (DOF). Finally, simulation results verify the effectiveness of the proposed method.展开更多
基金Project supported by the National Natural Science Foundation of China(No.61503408)。
文摘Phased array (PA) radar is one of the most popular types of radar. In contrast to PA, the frequency diverse array (FDA) is a potential solution to suppress range-related interference because of its time-range-angle-dependent beampattern. However, the range-angle coupling inherent in the FDA transmit beampattern may degrade the output signal-to-interference-plus-noise ratio (SINR). We propose a dot-shaped beamforming method based on the analyzed four subarray-based FDAs and subarray-based planar FDAs using a sinusoidally increasing frequency offset with elements transmitting at multiple frequencies. The numerical results show that the proposed approach outperforms the existing log-FDA with logarithmical frequency offset in transmit energy focus, sidelobe suppression, and array resolution. Comparative simulation results validate the effectiveness of the proposed method.
文摘频率分集阵列(Frequency Diverse Array, FDA)是作为一种全新的电扫描雷达体制,其方向图所具有的时间-距离-角度三维相关特性在电子对抗和安全通信等领域有广阔的应用前景。一维均匀线性FDA阵列(Uniform Linear Array Frequency Diverse Array, ULFDA)的发射方向图存在角度-距离耦合问题,针对这一问题,在对称子阵密度锥削阵结构的基础上,通过正弦频控函数取代原有的均匀线性函数,得到了FDA的点状波束指向控制方法。此外,针对FDA方向图的时变问题,得到了基于子阵结构的密度锥削阵sin-FDA主波束在角度维指向固定、距离维变化时的结论。
文摘针对雷达电子战中,敌方无源探测雷达通过接收干扰机信号实现测向定位,威胁我方干扰机安全的问题,提出一种基于频率分集阵列(Frequency Diverse Array,FDA)的测向交叉定位欺骗技术。首先在建立FDA阵列模型的基础上,通过欧拉公式得到采用非线性频控函数的FDA阵列因子及相位方向图;然后推导了FDA阵列作用于干涉仪测得的信号到达角β、虚拟发射机在X轴的坐标位置x;接着,以干涉仪测向欺骗为基础,分析了FDA干扰机对测向交叉定位系统的欺骗原理及定位精度。仿真结果表明:通过合理地对载频、阵元数目、频偏的选择可以较好地实现在远场条件下FDA阵列对干涉仪测向的欺骗效果;在合理选择其他参数的同时,测向精度越高、定位模糊区面积越小,且定位虚拟干扰机位置始终落在50%CEP半径之外。
文摘频率分集阵列(Frequency Diverse Array,简称FDA)在埋体管线的探测识别与成像中具有很大优势,利用其灵活的波束控制和信号处理性能,能够摆脱传统阵列发射信号限制,灵活接收和处理复杂信号。通过发出窄带信号进而获得宽带信号探测参数,大大降低操作成本,实现高效率、高精度、高性价比三维立体成像。现如今埋体管线探测成为城市发展中不可避免的痛点,小埋藏体检测成像更是难点问题。文章提出一种基于多进多出技术(Multiple-Input Multiple-Output,简称MIMO)的频率分集阵列三维合成孔径雷达(3D-FDA-MAR)成像方法,并将MIMO阵列引入频率分集阵列实现三维成像,建立了MIMO-FDA三维形貌成像模型。该多进多出频率分集阵列在三维空间中能够随平台运动而运动,在沿航向处得到综合孔径,根据切航向阵列能够获得仿真频率分集阵列平面,从而得到目标物成像的三维立体效果,实现精准定位,全空间透视探测,智能3D成像,小埋藏体的精准检测诊断。
文摘共形频控多输入多输出(Frequency diverse array multiple input and multiple output,FDA-MIMO)系统的波束图由俯仰角、方位角、距离三维信息控制,能够进一步提高系统的自由度。随着人们对高分辨目标探测性能以及高空气动力学性能的需求增加,研究共形FDA-MIMO阵列波束图综合方法很有意义。本文详细推导了共形FDAMIMO系统的信号建模和波束图分析的数学过程,并提出一种基于参数迭代的发射接收联合权向量优化算法以得到高分辨率的波束图。该算法首先建立一个二阶锥规划(Second-order cone programming,SOCP)模型,并利用交替方向乘子法(Alternating direction method of multipliers,ADMM)实现参数分离,原问题分为两个子问题。最后分别对各个子问题进行优化。数值仿真表明所提算法相比于传统算法性能更有优势,同时其收敛性得到验证。此外,为进一步分析系统特性,本文讨论了不同系统参数,如发射阵列阵元数、接收阵列阵元数、频控阵频偏大小以及不同频偏方式对本文所提算法下的波束图影响。
基金supported by the National Natural Science Foundation of China(61301282)
文摘The seriously range-ambiguous clutter is one of the main problems in clutter suppression for hypersonic vehicle-borne forward-looking radar. An approach based on the frequency diverse array (FDA) technique is proposed to mitigate the range ambiguous clutter. The frequency increment is designed to distinguish the clutter at ambiguous ranges and suppress the clutter by using a subspace projection algorithm. On the platform with high altitude or limited array antennas, the proposed method performs better for its independence of the elevation degrees-of-freedom (DOF). Finally, simulation results verify the effectiveness of the proposed method.
