基于SKA1-low的数字波束形成技术

Digital Beamforming Techniques Based on SKA1-low

为配合我国参与平方公里射电阵(SKA)项目,深入理解数字波束形成条件下的射电干涉观测和相应数据处理算法,提出了基于多相滤波器组信道化数字移相波束形成和基于分数阶时延滤波器数字波束形成两个技术算法,前者使用互相关法求解相移量来提高波束指向精度,后者是传统算法与射电观测理论的有效结合。首先,详细介绍了算法的理论推导并分析了它们的优缺点;然后,通过仿真实验验证了这两个算法的正确性,仿真结果表明基于多相滤波器组信道化数字移相波束形成算法相比传统算法具有一定的优越性;最后,分析了不同阶数时延滤波器对波束形成的影响并得出了相应结论。这些仿真结果及结论可为从事SKA项目的科研人员提供参考。

In order to coordinate China ＇ s participation in Square Kilometre Array （ SKA） and gain depth un-derstanding of radio interferometry and data processing algorithm based on digital beamforming, the polyphase filter bank channels based digital phase shift and the fractional delay filter based digital beamforming algo-rithms are proposed in this paper. The former algorithm solves the phase shift amount by using a cross-corre-lation method to improve the beam pointing accuracy. The latter algorithm is an effective combination of tradi-tional algorithm and radio observations theory. Firstly, the principles of the proposed algorithms are derived and the advantages and drawbacks of the two algorithms are analyzed. Secondly, the simulation results are shown to verify the correctness of the proposed algorithms. Simulation results indicate that the proposed poly-phase filter bank channels based digital phase shift beamforming has certain advantages in comparison with traditional algorithm. Finally, the effect of delay filter of different orders on beamforming is also analyzed. These simulation results and conclusions will provide reference for the researchers of SKA project.