Implementation of an FPGA-based traffic light controller for urban road intersections

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Authors: Laura Fernández Gómez, Daniel K Hoffman, Sofia R Conti
Cited by: 0

Abstract

Rapid urbanization has significantly increased vehicular density at road intersections, leading to congestion, delays, and safety concerns. Conventional traffic light controllers based on fixed-time microcontroller or relay logic often lack flexibility, scalability, and real-time responsiveness required for modern traffic management. Field Programmable Gate Arrays (FPGAs) offer a promising alternative due to their parallel processing capability, reconfigurability, high speed, and deterministic timing behavior. This research presents the design and implementation of an FPGA-based traffic light controller tailored for urban road intersections. The proposed system employs a finite state machine architecture to manage multiple traffic phases, including red, yellow, and green signals, with precise timing control. Hardware Description Language (HDL) is used to model the controller logic, enabling modular design and ease of modification. Simulation and synthesis are performed to validate functional correctness, timing accuracy, and resource utilization. The design supports extendibility for pedestrian crossings, emergency vehicle priority, and sensor-based traffic density inputs. Compared to conventional controllers, the FPGA-based solution demonstrates improved reliability, reduced propagation delay, and enhanced adaptability to varying traffic conditions. The deterministic nature of FPGA execution ensures predictable signal transitions, which is critical for traffic safety. Additionally, the proposed implementation minimizes hardware complexity by integrating control logic into a single programmable device. This work highlights the suitability of FPGA technology for intelligent traffic control applications in smart city environments. The results indicate that FPGA-based traffic light controllers can serve as a robust platform for future traffic management systems requiring real-time operation, scalability, and integration with advanced sensing and communication modules. The research provides a foundation for further research on adaptive and AI-assisted traffic control using reconfigurable hardware platforms in complex urban scenarios.

Fields of Study & Subjects

Traffic control and management Vehicular Ad Hoc Networks (VANETs) Transportation Safety and Impact Analysis

Publication details

Journal / source
International Journal of Circuit Computing and Networking
Volume
7
Issue
1
Pages
32–36
Publication date
1 January 2026