College - Author 1
College of Engineering
Department - Author 1
Electrical Engineering Department
Degree Name - Author 1
BS in Electrical Engineering
College - Author 2
College of Engineering
Department - Author 2
Electrical Engineering Department
Degree - Author 2
BS in Electrical Engineering
Date
6-2025
Primary Advisor
Payam Nayeri, College of Engineering, Electrical Engineering Department
Abstract/Summary
This senior project presents the development of a communication network designed to remotely control and program a distributed digital antenna array for autonomous synchronization and calibration. The system facilitates command transmission using a custom BPSK communication protocol operating in the UHF band (430–450 MHz) and employs a two-tone waveform to extract frequency, phase, and timing offsets between array nodes. These offsets are critical for aligning received signals in preparation for digital beamforming. The array comprises four nodes: three aerial units and one ground-based control unit. Each node is built using a LimeSDR Mini 2.0, Raspberry Pi, portable battery pack, and powered USB hub. GNU Radio is used to construct and manage the BPSK and two-tone signal chains, while higher-level Python scripts implement a finite state machine to coordinate timing, control logic, and data exchange. This system represents the foundational hardware layer for a larger multi-year project focused on implementing cost-effective, software-defined digital beamforming arrays. This research not only presents a novel implementation of distributed digital arrays but also enhances target localization accuracy through the creation of a coherent and calibrated digital beamformer. The findings have the potential to significantly improve the performance of distributed arrays in critical applications such as disaster response, defense, and other scenarios where access to nodes is limited.
URL: https://digitalcommons.calpoly.edu/eesp/696