基于SKA1-low的数字波束形成技术
|
摘要
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 understanding 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 algorithms are proposed in this paper. The former algorithm solves the phase shift amount by using a cross- correlation method to improve the beam pointing accuracy. The latter algorithm is an effective combination of traditional 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 polyphase 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.
In order to coordinate China's participation in Square Kilometre Array( SKA) and gain depth understanding 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 algorithms are proposed in this paper. The former algorithm solves the phase shift amount by using a cross- correlation method to improve the beam pointing accuracy. The latter algorithm is an effective combination of traditional 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 polyphase 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.
引文
[1]彭勃,金乘进,杜彪,等.持续参与世界最大综合孔径望远镜SKA国际合作[J].中国科学:物理学力学天文学,2012,42(12):1292-1307.PENG Bo,JIN Chengjin,DU Biao,et al.China's participation in the SKA the world's largest synthesis radio telescope[J].Scientia Sinica:Pysica,Mechanica&Astronomica,2012,42(12):1292-1307.(in Chinese)
[2]TASSE C,DIEPEN G V,TOL S V D,et al.LOFAR calibration and wide-field imaging[J].Comptes Rendus Physique,2012,13(1):28-32.
[3]HAARLEM M P V,WISE M W,GUNST A W,et al.LOFAR:the low-frequency array[J].Physics,2013,556(7):629-635.
[4]KAPLAN D L,TINGAY S J,MANOHARAN P K,et al.Murchison widefield array observations of anomalous variability:a serendipitous night-time detection of interplanetary scintillation[J].The Astrophysical Journal Letters,2015,809(1):1-7.
[5]ZARB-ADAMI K,FAULKNER A,KANT G W,et al.Beamforming techniques for large-N aperture arrays[C]//Proceedings of 2010 IEEE International Symposium on Phased Array Systems and Technology(ARRAY).Walcham,MA:IEEE,2010:883-890.
[6]MOL J D,ROMEIN J W.The LOFAR beam former:implementation and performance analysis[J].Lecture Notes in Computer Science,2011,6853(2):328-339.
[7]TINGAY S J,GOEKE R,BOWMAN J D,et al.The murchison widefield array:the square kilometre array precursor at low radio frequencies[J].Publications of the Astronomical Society of Australia,2013,30(30):109-121.
[8]SHAKIR M Z,DURRANI T S.Narrowband beamforming algorithm for smart antennas[C]//Proceedings of 2007International Bhurban Conference on Applied Sciences&Technology.Islamabad:IEEE,2007:49-54.
[9]陈岚,张秀忠.用于VLBI数字基带转换的多相滤波器技术研究[J].天文学进展,2008,26(1):87-94.CHEN Lan,ZHANG Xiuzhong.The study of DBBC based on poly-phase filter banks and FFT in VLBI[J].Progress in Astronomy,2008,26(1):87-94.(in Chinese)
[10]ARMSTRONG R,HICKISH J,ZARB ADAMI K,et al.A digital broadband beamforming architecture for 2-PAD[J].Physics,2010,13(3):185-189.
[11]VALIMAKI V,LAAKSO T.Fractional delay digital filters[C]//Proceedings of 1993 IEEE International Symposium on Circuits and Systems.Chicago,IL:IEEE,1993:355-359.
[2]TASSE C,DIEPEN G V,TOL S V D,et al.LOFAR calibration and wide-field imaging[J].Comptes Rendus Physique,2012,13(1):28-32.
[3]HAARLEM M P V,WISE M W,GUNST A W,et al.LOFAR:the low-frequency array[J].Physics,2013,556(7):629-635.
[4]KAPLAN D L,TINGAY S J,MANOHARAN P K,et al.Murchison widefield array observations of anomalous variability:a serendipitous night-time detection of interplanetary scintillation[J].The Astrophysical Journal Letters,2015,809(1):1-7.
[5]ZARB-ADAMI K,FAULKNER A,KANT G W,et al.Beamforming techniques for large-N aperture arrays[C]//Proceedings of 2010 IEEE International Symposium on Phased Array Systems and Technology(ARRAY).Walcham,MA:IEEE,2010:883-890.
[6]MOL J D,ROMEIN J W.The LOFAR beam former:implementation and performance analysis[J].Lecture Notes in Computer Science,2011,6853(2):328-339.
[7]TINGAY S J,GOEKE R,BOWMAN J D,et al.The murchison widefield array:the square kilometre array precursor at low radio frequencies[J].Publications of the Astronomical Society of Australia,2013,30(30):109-121.
[8]SHAKIR M Z,DURRANI T S.Narrowband beamforming algorithm for smart antennas[C]//Proceedings of 2007International Bhurban Conference on Applied Sciences&Technology.Islamabad:IEEE,2007:49-54.
[9]陈岚,张秀忠.用于VLBI数字基带转换的多相滤波器技术研究[J].天文学进展,2008,26(1):87-94.CHEN Lan,ZHANG Xiuzhong.The study of DBBC based on poly-phase filter banks and FFT in VLBI[J].Progress in Astronomy,2008,26(1):87-94.(in Chinese)
[10]ARMSTRONG R,HICKISH J,ZARB ADAMI K,et al.A digital broadband beamforming architecture for 2-PAD[J].Physics,2010,13(3):185-189.
[11]VALIMAKI V,LAAKSO T.Fractional delay digital filters[C]//Proceedings of 1993 IEEE International Symposium on Circuits and Systems.Chicago,IL:IEEE,1993:355-359.