Two-step compressed acquisition method for Doppler frequency and Doppler rate estimation in high-dynamic and weak signal environments

• 作者: WU Chao LIU Erxiao JIAN Zhihua
• 来源期刊: 系统工程与电子技术（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: ELECTRONICS TECHNOLOGY
• 页码范围: 831-840
• 页数: 10页
• 语种: 英文
• DOI: 10.23919/JSEE.2021.000072

摘要

To acquire global navigation satellite system (GNSS) signals means four-dimension acquisition of bit transition, Dop-pler frequency, Doppler rate, and code phase in high-dynamic and weak signal environments, which needs a high computation-al cost. To reduce the computations, this paper proposes a two-step compressed acquisition method (TCAM) for the post-correla-tion signal parameters estimation. Compared with the fast Fouri-er transform (FFT) based methods, TCAM uses fewer frequency search points. In this way, the proposed method reduces com-plex multiplications, and uses real multiplications instead of im-proving the accuracy of the Doppler frequency and the Doppler rate. Furthermore, the differential process between two adjacent milliseconds is used for avoiding the impact of bit transition and the Doppler frequency on the integration peak. The results demonstrate that due to the reduction of complex multiplica-tions, the computational cost of TCAM is lower than that of the FFT based method under the same signal to noise ratio (SNR).