yeyi58095/iot_lab

This repository is a collection of course labs and reports, not one integrated application. Its work covers ECG/PPG signal analysis, sensor-monitoring and plotting projects, BLE-based experiments, and an ultrasonic-ranging capstone. The clearest executable workflow is the ECG analysis script reading the data_3 spreadsheet and displaying signal/envelope and frequency plots. Other project files are mostly opaque App Inventor archives or reports, so their internal wiring and runtime behavior cannot be established from the sampled source.