A frequency-domain segmental shift average periodogram acquisition algorithm for GPS signals with low SNR and high dynamic was proposed. First, the parallel rough compensation of Doppler frequency rate and C/A code phase as well as segmental FFT was applied with the received signal. Second, the compensation interval was extended to precise estimation interval based on the number of data segments. Third, the branch with the nearest compensation value was chosen as the estimation branch of each estimation value and the difference of two values was reduced by segmental fre-quency spectrum shift. The correlation value of each estimation branch was obtained by non-coherent accumulation of all shifted frequency spectrums. Last, the maximum correlation value was sent to a constant false alarm rate detector to de-termine whether the acquisition was success. The results show that compared with the traditional periodogram algorithm, the proposed algorithm has much lower computational complexity and a little performance loss.%针对高动态低信噪比环境下的GPS信号捕获问题，提出一种频域分段移位平均周期图算法。首先，对接收信号进行频率斜升和码相位二维并行粗补偿并对各补偿支路进行分段快速傅里叶变换；其次，根据参与捕获的有效数据段长度将频域补偿间隔扩展为更为精细的估计间隔；然后，找到与各参数估计值最接近的补偿支路，根据估计值与实际补偿值之间差值对各数据段的频谱进行旋转移位，并将移位之后的频谱进行非相干累加以得到各估计值所对应的相关峰；最后，对相关峰的峰值进行恒虚警检测以确定捕获是否成功。仿真结果表明，与平均周期图算法相比，所提算法捕获性能略有下降，但计算复杂度大幅降低。
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