无源定位技术无需主动发射电磁波，而是通过被动接收辐射源信号实现定位，广泛 应用于远程预警、地面防空和电磁环境监测等领域。单站无源定位通常利用阵列天线来 获取辐射源信号，当信号从某一方向到达天线阵列时，阵列中各个阵元接收到的信号会 存在相位差，通过构建辐射源二维位置与相位差之间的函数关系，对不同阵元接收到的 信号进行波束形成实现定位。该方法在不同时刻对信号的积累是幅度积累，在低信噪比 条件下容易受到噪声影响，导致定位误差较大。因此，本论文采用的合成孔径技术对不同时刻接收的定位结果进行相干积累，实现辐射源的高精度无源定位。论文的研究围绕基于运动单平台的信号源相干定位方法展开，论文主要工作如下：

（1）针对斜视模式下多普勒中心偏移导致方位定位结果出现偏差的问题，提出了 一种基于斜视合成孔径的无源定位方法，实现了辐射源的二维高精度定位。根据接收平台与辐射源间距离的变化构建了全孔径模式下的斜视定位几何模型。通过线性相位调制对接收信号进行多普勒补偿，有效校正了多普勒中心频率的偏移。采用匹配滤波方式对辐射源进行方位聚焦，根据聚焦结果，得到辐射源位置。为了处理图像畸变的问题，通过几何校正的方法，消除了方位偏差，得到了精确的定位结果。仿真分析和蒙特卡洛实验结果表明，该方法能够在低信噪比下有效提升定位精度。

（2）针对传统一维合成孔径技术无法提供目标的高度信息导致难以满足三维定位应用需求，提出了一种基于圆周轨迹合成孔径的无源定位方法，实现了辐射源的三维高精度定位。根据接收平台与辐射源间距离的变化构建了圆周合成孔径定位几何模型。建立了辐射源三维位置与圆周阵列接收相位之间的参数映射关系。在此基础上，构造最大似然代价函数，同时考虑到瞬时多普勒的影响，引入补偿函数补偿了多普勒。最终，通过代价函数搜索峰值实现目标三维定位。仿真分析与蒙特卡洛实验结果表明，该方法在低信噪比条件下通过相干处理提高了定位精度。此外，还对分辨率性能进行仿真分析， 进一步验证了所提方法的理论推导的正确性。

Passive positioning technology does not need to actively transmit electromagnetic waves, but through the passive reception of radiation source signals to achieve positioning, which is widely used in remote warning, ground air defense and electromagnetic environment monitoring and other fields. Single station passive positioning usually use array antenna to obtain the radiation source signal, when the signal arrives at the antenna array from a certain direction, there will be a phase difference between the signals received by each array element in the array, through the construction of the two-dimensional position of the radiation source and the phase difference of the functional relationship between the beam formation of the signals received by the different array elements according to the functional relationship to achieve positioning. This method accumulates the signals at different moments with amplitude accumulation, which is easily affected by noise under low signal-to-noise ratio conditions, resulting in large positioning errors. Therefore, the synthetic aperture technique adopted in this thesis coherently accumulates the localization results received at different moments to achieve high-precision passive localization of the radiation source. The research of the thesis revolves around the coherent positioning method of signal source based on motion single platform. The main work of the thesis is as follows:

(1) To address the azimuth localization errors caused by Doppler centroid shifts under squint-mode configurations, a passive positioning algorithm based on squint synthetic aperture is proposed to achieve two-dimensional high-precision positioning of the radiation source. According to the change of the distance between the receiving platform and the radiation source, the squint positioning geometric model in full aperture mode is constructed. The Doppler compensation of the received signal is performed by linear phase modulation, which effectively corrects the offset of the Doppler center frequency. The radiation source is focused in azimuth by the matched filtering method, and the position of the radiation source is obtained according to the focusing result. In order to deal with the problem of image distortion, the azimuth deviation is eliminated by the method of geometric correction, and an accurate positioning result is obtained. The simulation analysis and Monte Carlo experiment results show that the algorithm can effectively improve the positioning accuracy under low signal-to-noise ratio.

(2) To address the limitations of traditional one-dimensional synthetic aperture techniques, which fail to provide accurate elevation information and therefore cannot meet the requirements of three-dimensional localization applications. A passive positioning algorithm based on circular trajectory synthetic aperture is proposed to achieve three-dimensional high-precision positioning of the radiation source. The circular synthetic aperture positioning geometric model is constructed according to the change of the distance between the receiving platform and the radiation source. The parameter mapping relationship between the three-dimensional position of the radiation source and the receiving phase of the circular array is established. On this basis, the maximum likelihood cost function is constructed, and the influence of instantaneous Doppler is taken into account, and the compensation function is introduced to compensate for the Doppler. Finally, the three-dimensional positioning of the target is achieved by searching the peak value through the cost function. The simulation analysis and Monte Carlo experimental results show that this method improves the positioning accuracy through coherent processing under low signal-to-noise ratio conditions. In addition, the resolution performance is simulated and analyzed to further verify the correctness of the theoretical derivation of the proposed algorithm.