A custom RF communication module built for secure, long-range data links — combining AES-encrypted packet transmission, adaptive range extension, and a real-time diagnostics link for signal health monitoring.
Standard Wi-Fi and Bluetooth modules fall short in two common scenarios: long range outdoor links, and situations where you genuinely need the transmission itself encrypted rather than relying on a higher-level protocol. This project builds a dedicated point-to-point RF box to solve both.
Two identical enclosures — a transmitter and receiver — communicate over a sub-GHz RF link with a custom packet format. Every payload is encrypted with AES-128 before transmission, and a rolling sequence number guards against replay attacks. A built-in diagnostics channel reports RSSI, packet loss, and link quality back to both ends continuously.
The result is a general-purpose secure wireless bridge that's been used for everything from remote sensor telemetry to a simple encrypted walkie-talkie-style data link between two lab benches.
Every packet is encrypted end-to-end before transmission, with per-session key rotation.
Adaptive spreading factor trades throughput for range, reaching over 1.5km line-of-sight.
Live RSSI, SNR, and packet-loss reporting streamed alongside the main data channel.
Rolling sequence numbers reject duplicate or replayed packets automatically.
Radio sleeps between transmission windows, extending field deployment battery life.
Simple framed packet structure makes it easy to carry sensor data, text, or commands.
Watch simulated encrypted packets travel between the TX and RX nodes. Click the lock icon to toggle encryption on and off.
I take on consultancy and freelance electronics projects — from prototype to production.
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