College - Author 1
College of Engineering
Department - Author 1
Electrical Engineering Department
Degree Name - Author 1
BS in Electrical Engineering
Date
6-2026
Primary Advisor
Dean Arakaki, College of Engineering, Electrical Engineering Department
Abstract/Summary
Animal tracking collars transmit very-high-frequency (VHF) beacon signals so researchers can locate tagged wildlife in terrain where direct visual tracking is difficult. This project develops a radio-frequency (RF) wildlife tracking prototype in which a UAV carries a receiving antenna and receiver over the search area to detect the collar signal and send measurements to a ground station. A transmitter test device was built to emulate a tracking collar. An STM32 microcontroller reads keypad input, controls a digital-to-analog converter (DAC), tunes a voltage-controlled oscillator (VCO) to the selected VHF frequency, and sends the RF signal through an amplifier and antenna. The receiver uses an RTL software-defined radio (RTL-SDR) and Raspberry Pi to calculate received signal strength indicator (RSSI), a relative measure of received RF signal strength. Digi XBee radio modules provide telemetry by wirelessly sending RSSI data to the ground-station graphical user interface (GUI), which displays RSSI, estimated distance, and bearing. Testing covered approximately 140.0–180.0 MHz. The amplified RF output power was estimated at +22.0 dBm, where dBm is referenced to 1 mW. RSSI updates were displayed at approximately 2.0 Hz, and distance estimation was evaluated over an approximate 10.0 m separation between the UAV Yagi-Uda receiving antenna and the transmitter test device antenna. Remaining work includes collar-like beacon timing, outdoor signal-strength testing, direct output-power verification, and UAV flight integration.
URL: https://digitalcommons.calpoly.edu/eesp/734