Signal Upper and Lower Envelope Analysis

Frequently on technical forums, users request programs for calculating signal upper and lower envelopes. This MATLAB implementation provides a comprehensive solution for envelope analysis.

It's gratifying to see widespread interest in signal envelope analysis tools. Signal envelopes serve as valuable instruments for characterizing signal features and trends. Our MATLAB program implements envelope calculation and visualization using Hilbert transform techniques combined with peak detection algorithms. The core functionality includes envelope extraction through analytic signal processing, where the envelope is computed as the magnitude of the analytic signal obtained via the Hilbert transform. This approach ensures accurate envelope detection for various signal types.

The program features straightforward operation: simply input your signal data vector and execute the script. The algorithm automatically computes upper and lower envelopes using moving window peak detection with configurable window sizes. Results are displayed graphically with customizable plot parameters. Users can modify envelope precision through adjustable smoothing filters, incorporate additional signal characteristics like instantaneous frequency, or implement threshold-based envelope refinement.

We hope this tool proves beneficial for signal processing research and applications. The code structure facilitates easy modification, with key functions including hilbert() for analytic signal generation, envelope() for magnitude calculation, and findpeaks() for extreme value detection. For questions or enhancement suggestions, please feel free to contact us. Thank you for your support!