THE WAVELET EXTRAPOLAfION TECHNIQUEUSED IN TRANSFORM RECONSTRUCTION FORCOMPUTERIZED IONOSPHERIC TOMOGRAPHY
-
摘要: 电离层CT技术由于数据采集系统结构的局限性,致使所得数据不完全,伪投影中采样不均匀,频域谱值不完全。若用直接Fourier方法重建,必须对伪投影采样施以均匀化和在二维频域内进行估值。本文参照已有的Fourier外推技术,提出小波外推技术。理论分析和重建结果都说明小波外推技术具有较多优越性。
-
关键词:
- 电离层CT技术 /
- Fourier外推技术 /
- 小波外推技术
Abstract: The limitations caused by data acquisition system geometry in computerizedionospheric tomography (CIT) in general bring some problems such as incompletedata obtained, nonuniform samples in pseudo-projections, incomplete spectrum infrequency domain. If direct FOurier method is used for reconstruction, the nonuniform samples in pseudo-projections must be uniformed and unknown region in twodimensional frequency domain must be estimated. With reference of Fourier extrapolation technique, the wavelet extrapolation technique is presented in this paper.Theoretical analysis and simulation are also shown, they demonstrate inverse abilityand feasibility of the method. Both theoretical analysis and reconstruction resultsshow much superiority of the wavelet transform extrapolation technique.
点击查看大图
计量
- 文章访问数: 1718
- HTML全文浏览量: 60
- PDF下载量: 956
- 被引次数: 0