Beam Spot Formation After Laser Beam Passes Through Lens in Laser Optics
Laser beam spot formation through optical lenses and its intensity distribution analysis
Fast Algorithm for Adaptive Chirplet Decomposition
A rapid algorithm for adaptive chirplet decomposition, addressing the challenges of numerous unknown parameters and implementation difficulties. This algorithm computes the quadratic phase function of signals to determine energy concentration along chirp rate curves, enabling simultaneous estimation of chirplet parameters (chirp rate, time center, and amplitude) via spectral peak detection. Initial frequency and bandwidth estimates are obtained through de-chirping techniques. The effectiveness of this method is validated through simulation results.
Wavelet Transform and Energy Distribution Characteristics of Noisy Signals for Image Denoising
Based on the energy distribution characteristics of wavelet transform and noisy signals, we propose a method that first decomposes noisy images using multi-scale wavelet transform, calculates the noise variance and thresholds for high-frequency coefficients at each scale, processes the high-frequency coefficients using these scale-specific thresholds, and then reconstructs the image using wavelet coefficients to achieve effective image denoising.