In view of the inconsistency of channel gains and a large amount of interference noise in Solar Broadband Radio Spectrometer(SBRS) observation data,they will seriously affect the analysis of SBRS data.In this paper,a ...In view of the inconsistency of channel gains and a large amount of interference noise in Solar Broadband Radio Spectrometer(SBRS) observation data,they will seriously affect the analysis of SBRS data.In this paper,a method of Radio Frequency Interference(RFI) detection and mitigation for SBRS observation data is reported.Firstly,the SBRS observation data are preprocessed,a part of the observation data was selected to calculate the mean and variance to achieve the normalization of the entire observation data,which can avoid the influence of strong noise on the normalization result.Furthermore,we proposed an adaptive threshold RFI detection method based on fusion wavelet transform reconstruction and an RFI elimination method based on neighborhood weighted filling.It is worth mentioning that to detect RFI interference signals of different magnitudes,we adopted an iterative approach to the RFI detection and mitigation process.Through qualitative analysis of real observation data and quantitative analysis of simulated data,it is shown that the method proposed in this paper can effectively eliminate RFI in SBRS observation data,and improve the quality of observation data for further scientific analysis.展开更多
传统弹跳射线(shooting and bouncing rays,SBR)方法采取按均匀射线管的方式进行射线追踪,因此,在计算电大尺寸复杂目标多次反射时,需要处理海量射线,计算效率极低,应用上受到很大限制。提出了一种基于复杂目标不规则三角网(triangle ir...传统弹跳射线(shooting and bouncing rays,SBR)方法采取按均匀射线管的方式进行射线追踪,因此,在计算电大尺寸复杂目标多次反射时,需要处理海量射线,计算效率极低,应用上受到很大限制。提出了一种基于复杂目标不规则三角网(triangle irregular network,TIN)模型的自适应射线管分裂算法(adaptive ray tubesplitting algorithm,ARTSA),利用TIN模型信息动态生成非均匀初始射线管,经过与模型三角面元的求交、多边形裁剪和三角化处理,将初始射线管自适应分裂成多个子射线管,利用口面积分(aperture integral,AI)法计算各子射线管的多次反射场,通过相干叠加获得目标多次反射贡献。与传统SBR方法相比,在相同计算精度下,所提算法能极大地减少射线追踪数量,显著提高计算电大尺寸复杂目标多次反射的效率。展开更多
基金funded by the Open Research Program of CAS Key Laboratory of Solar Activity,National Astronomical Observatories (KLSA201909)the National Natural Science Foundation of China (Nos.11773072 and 11873027)Yunnan Fundamental Research Projects (202001AT070135)。
文摘In view of the inconsistency of channel gains and a large amount of interference noise in Solar Broadband Radio Spectrometer(SBRS) observation data,they will seriously affect the analysis of SBRS data.In this paper,a method of Radio Frequency Interference(RFI) detection and mitigation for SBRS observation data is reported.Firstly,the SBRS observation data are preprocessed,a part of the observation data was selected to calculate the mean and variance to achieve the normalization of the entire observation data,which can avoid the influence of strong noise on the normalization result.Furthermore,we proposed an adaptive threshold RFI detection method based on fusion wavelet transform reconstruction and an RFI elimination method based on neighborhood weighted filling.It is worth mentioning that to detect RFI interference signals of different magnitudes,we adopted an iterative approach to the RFI detection and mitigation process.Through qualitative analysis of real observation data and quantitative analysis of simulated data,it is shown that the method proposed in this paper can effectively eliminate RFI in SBRS observation data,and improve the quality of observation data for further scientific analysis.
文摘传统弹跳射线(shooting and bouncing rays,SBR)方法采取按均匀射线管的方式进行射线追踪,因此,在计算电大尺寸复杂目标多次反射时,需要处理海量射线,计算效率极低,应用上受到很大限制。提出了一种基于复杂目标不规则三角网(triangle irregular network,TIN)模型的自适应射线管分裂算法(adaptive ray tubesplitting algorithm,ARTSA),利用TIN模型信息动态生成非均匀初始射线管,经过与模型三角面元的求交、多边形裁剪和三角化处理,将初始射线管自适应分裂成多个子射线管,利用口面积分(aperture integral,AI)法计算各子射线管的多次反射场,通过相干叠加获得目标多次反射贡献。与传统SBR方法相比,在相同计算精度下,所提算法能极大地减少射线追踪数量,显著提高计算电大尺寸复杂目标多次反射的效率。