Journals
  Publication Years
  Keywords
Search within results Open Search
Please wait a minute...
For Selected: Toggle Thumbnails
Global-scale radar data restoration algorithm based on total variation and low-rank group sparsity
Chenyu GE, Liang DONG, Yikun XU, Yi CHANG, Hongming ZHANG
Journal of Computer Applications    2021, 41 (11): 3353-3361.   DOI: 10.11772/j.issn.1001-9081.2020122047
Abstract455)   HTML10)    PDF (3343KB)(374)       Save

The mixed noise formed by a large number of spikes, speckles and multi-directional stripe errors in Shuttle Radar Terrain Mission (SRTM) will cause serious interference to the subsequent applications. In order to solve the problem, a Low-Rank Group Sparsity_Total Variation (LRGS_TV) algorithm was proposed. Firstly, the uniqueness of the data in the local range low-rank direction was used to regularize the global multi-directional stripe error structure, and the variational idea was used to perform unidirectional constraints. Secondly, the non-local self-similarity of the weighted kernel norm was used to eliminate the random noise, and the Total Variation (TV) regularity was combined to constrain the data gradient, so as to reduce the difference of local range changes. Finally, the low-rank group sparse model was solved by the alternating direction multiplier optimization to ensure the convergence of model. Quantitative evaluation shows that, compared with four algorithms such as TV, Unidirectional Total Variation (UTV), Low-Rank-based Single-Image Decomposition (LRSID) and Low-Rank Group Sparsity (LRGS) model, the proposed LRGS_TV has the Peak Signal-to-Noise Ratio (PSNR) of 38.53 dB and the Structural SIMilarity (SSIM) of 0.97, which are both better than the comparison algorithms. At the same time, the slope and aspect results show that after LRGS_TV processing, the subsequent applications of the data can be significantly improved. The experimental results show that, the proposed LRGS_TV can repair the original data better while ensuring that the terrain contour features are basically unchanged, and can provide important support to the reliability improvement and subsequent applications of SRTM.

Table and Figures | Reference | Related Articles | Metrics
Weight modification accumulated epochs RAIM algorithm based on self-adaptive strategy
HUANG Guorong CHANG Cheng HAO Shunyi CHANG Yanan XU Gang
Journal of Computer Applications    2013, 33 (08): 2366-2369.  
Abstract613)      PDF (594KB)(501)       Save
The conventional Receiver Autonomous Integrity Monitoring (RAIM) algorithm is limited when detecting weak pseudo-range bias under gradual change because of its longer detection delay and higher miss detection rate. A weight modification accumulated epochs parity vector RAIM algorithm based on self-adaptive strategy was presented to solve this problem. In this algorithm, the weight factor was obtained according to the single epoch fault degree to adjust the proportion of each epoch in the selected window to structure more effective detection statistics, and the size of the window was determined according to the repeated simulation experiments. The simulation results show that the proposed method can better detect weak pseudo-range bias under gradual change, compared to accumulated epoch and the conventional RAIM algorithm, the detection delay time declines by 16.67% and 56.52% respectively.
Related Articles | Metrics