Design & Implementation of a Portable RF Radiation Detector

This work presents the design and realization of a portable RF radiation detection system based on the envelope detection technique. The proposed system detects the presence of high-frequency electromagnetic radiation by converting RF signals into a measurable DC voltage using a diode-based rectifier and RC envelope detector. The detected signal is processed using an LM358 comparator to generate a digital output that drives a visual indicator. The circuit was first modelled and analysed using LTspice to evaluate transient response and signal behaviour across each stage, including rectification, filtering, and comparator switching. Simulation results confirm successful envelope extraction and threshold-based detection. The hardware implementation was developed and experimentally tested to validate practical performance. The prototype demonstrates reliable detection of nearby RF sources and provides a compact, low-cost solution for basic RF radiation monitoring applications.