Remote Operated Amateur Radio using Raspberry Pi and LimeSDR

This project presents the design and implementation of a portable, remotely programmable amateur radio system operating on the 2-meter and 70-cm bands. The system utilizes Raspberry Pi 5 and LimeSDR hardware to facilitate communication between aerial and ground units, allowing for efficient transmission and reception of synchronization and calibration waveforms. A custom communication protocol incorporating BPSK modulation and a two-tone signaling mechanism enables time-of-flight measurements for calculating distances between nodes. This low-cost solution has potential applications in civilian sectors, such as search and rescue operations, where accurate direction finding and target localization are critical. Full-duplex operation enhances the system's capability to conduct simultaneous transmission and reception, reducing latency and improving the reliability of time-of-flight data. Initial results demonstrate successful signal transmission and reception with high data accuracy. Future work includes enhancing error correction and implementing advanced waveform capture techniques for further system robustness.