Concerning that the Wiener filtering algorithm leads signal distortion with low Signal-to-Noise Ratio (SNR) when dealing with the noise of non-stationary speech signal, a new speech denoising algorithm named SSA-WF was proposed combining with Singular Spectrum Analysis (SSA) and Wiener Filtering (WF). To obtain the speech signal as smooth as possible, SSA was used to denoise the nonlinear and non-stationary speech signal to improve the SNR of the noisy speech. Then the processed signal was put into WF to further eliminate the high frequency noise that still existed in the speech signal. The simulation results from different intensity of background noise show that the proposed algorithm is superior to the traditional methods in SNR and Root-Mean-Square Error (RMSE). The results also demonstrate that the new algorithm can not only remove the background noise efficiently, but also reserve the details of the original signal, it is suitable for the denoising of nonlinear and non-stationary speech signal.
Since the compressive sampling of Block-Based Compressed Sensing (BCS) in spatial domain lacks of considering the global features of an image, image fusion based on conventional BCS sampling suffers from reduced quality and blocking artifacts during reconstruction. Firstly, the input images were sparsely represented by Contourlet Transform (CT), then the Contourlet Transform Block-Based Compressed Sensing (CTBCS) sampling was implemented in the CT domain. Secondly, the compressive samplings were fused by the rule of linear weighting. Finally, the fused image was reconstructed by Iterative Thresholding Projection (ITP) algorithm with consideration of blocking artifacts. The fusion method based on CTBCS was proposed for remote-sensing images, and the implementation algorithm was also presented in detail. In the simulation experiments, BCS and CTBCS were used for compressive sampling, then ITP algorithm was used for image reconstruction. The simulation results show that, compared with BCS, CTBCS sampling which considered the global characteristics has higher convergence speed, less computational complexity and higher reconstructing accuracy, the corresponding Peak Signal-to-Noise Ratio (PSNR) of recovery image is also higher. The real data tests indicate that the compressive fusion based on CTBCS achieves better result than that based on BCS. With very small amount of samples, the CTBCS-based compressive fusion can achieve a comparable result with fusion by the conventional CT method. Therefore, the proposed fusion method effectively implements the compressive fusion for the remote-sensing images with large amounts of data.
Aiming at the problem that the traditional nonlinear robust filtering will be severely degraded when the distribution of measurement noise deviates from the assumed Gaussian distribution, a new robust nonlinear Kalman filter based on M-estimation and detection method was proposed. The proposed robust filtering algorithm set a threshold using Chi-square test to delete mutation outliers, and modified the measurement update using M-estimation. Several conventional nonlinear filtering methods were evaluated under different measurement noises in terms of accuracy and stability. Under non-Gaussian noise and strong interference, the proposed algorithm outperforms the traditional robust algorithm with higher estimation accuracy by 25.5% and lower estimation covariance by 18.3%. The experimental results show that the proposed filtering algorithm can suppress the influence of non-Gaussian noise and strong interference, and increase the estimation accuracy and stability.
The separation method of the graph was proposed for improving destroy-resistance and throughput at the assumption of known user distribution. Link Weight Factor (LWF) that eclectically thinks over geography complexities, destroyresistance and portfolio is defined. Putting forward the intersection circle algorithm that seeks the feasible seat of nodes and virtual cell algorithm that seeks the service center.The Communication Station design closely combines with the geography information systems, therefore the result is feasible and available.