The orthogonal signals of multi-carrier-frequency emission and multiple antennas receipt module are used in SIAR radar.The corresponding received echo is equivalent to non-uniform spatial sampling after the frequency diversity process.As using the traditional Fourier transform will result in the target spectral with large sidelobe,the method presented in this paper firstly makes the preordering treatment for the position of the received antenna.Then,the Bayesian maximum posteriori estimation with l2-norm weighted constraint is utilized to achieve the equivalent uniform array echo.The simulations present the spectrum estimation in angle precision estimation of multiple targets under different SNRs,different virtual antenna numbers and different elevations.The estimation results confirm the advantage of SIAR radar both in array expansion and angle estimation.
ZHAO GuangHui,SHI GuangMing & ZHOU JiaShe Key Laboratory of Intelligent Perception and Image Understanding of Ministry of Education of China,Xidian University,Xi’an 710071,China
针对空间色噪声环境提出一种同时利用空域和时域信息的双基地MIMO雷达DOD(Direction of Departure)和DOA(Direction of Arrival)联合估计方法。该方法在时域高斯白噪声的假设下,将不同时刻的匹配滤波器输出进行互相关以消除空间色噪声的影响并获得空时互相关矩阵,然后基于传播算子方法构造一低维矩阵,利用其特征参数与待估参数的特定关系获得目标DOD(Direction of Departure)和DOA(Direction of Arrival)的联合估计。该方法能够有效克服空间色噪声的影响,所估计参数自动配对。与现有方法相比,其孔径损失小,具有更优的参数估计性能和最大可检测目标数,且对发射阵元个数没有特殊要求,具有更广泛的适用性。计算机仿真验证了本文方法的有效性。
该文针对空间色噪声环境提出一种基于时空结构的双基地MIMO雷达角度和多普勒频率联合估计方法,并推导了基于时空结构时角度和多普勒频率估计的克拉美-罗界(CRB)。该方法在时域噪声为高斯白噪声的假设下,首先将不同时刻匹配滤波器输出进行互相关以消除空间色噪声的影响,然后将相邻时刻匹配滤波器输出的时间相位差作为时间旋转因子,采用ESPRIT方法估计目标的DOD(Direction Of Departure),DOA(Direction Of Arrival)和多普勒频率。该方法能够克服空间色噪声的影响,所估计参数自动配对且无阵列孔径损失,并且适用于发射和接收阵列不满足平移不变结构的情况。计算机仿真验证了该文所提方法的有效性。
