Vehicle Access System Using UWB and Key Fob

Abstract

This paper presents a comprehensive analysis of Vehicle Access Systems based on Ultra-Wideband (UWB) technology integrated with secure digital key fobs. With the rapid advancement of intelligent transportation systems and connected vehicles, the demand for highly secure, reliable, and user-friendly vehicle access mechanisms has significantly increased. Conventional Remote Keyless Entry (RKE) systems, which primarily rely on radio frequency communication, are increasingly susceptible to security threats such as relay attacks, signal interception, and spoofing techniques, thereby compromising vehicle safety and user privacy. To address these limitations, UWB-based vehicle access systems have emerged as an advanced solution capable of providing precise distance estimation and robust authentication between the vehicle and the authorized key fob. By utilizing time-of-flight (ToF) measurements and secure ranging techniques, UWB technology enables accurate localization and ensures that access is granted only when the authenticated user is physically present within a defined proximity. This significantly enhances protection against unauthorized access while simultaneously improving operational convenience for users. The paper discusses the overall architecture and operational workflow of UWB-enabled vehicle access systems, including communication protocols, authentication procedures, ranging mechanisms, and system integration. Furthermore, it examines the technical implementation aspects, performance advantages, security enhancements, and practical challenges associated with deploying UWB technology in modern automotive applications. The study also highlights emerging developments and future research directions, emphasizing the role of UWB in shaping next-generation secure and intelligent vehicle access solutions.

Introduction

This study focuses on improving vehicle security systems by replacing traditional mechanical keys and vulnerable RF-based keyless entry systems with Ultra-Wideband (UWB) technology. Conventional systems suffer from security issues such as relay attacks, spoofing, and poor proximity detection, making them unreliable for modern smart vehicles.

UWB technology addresses these limitations by enabling highly accurate, low-power, short-range communication with centimeter-level distance measurement using Time-of-Flight (ToF). In the proposed system, a smart key fob and vehicle exchange encrypted signals, and access is granted only when the authorized key is detected within a safe physical range. This improves both security and convenience through passive entry and ignition.

The system is built using UWB modules (DWM1000), ESP32 microcontrollers, and CAN bus communication. It is tested through a hardware prototype that successfully demonstrates secure two-way ranging, authentication, and real-time status indication using LEDs for locked, waiting, and unlocked states. Experimental results show that the system provides accurate distance estimation, reliable communication, and strong resistance to unauthorized access compared to RF-based systems.

The literature review highlights growing industry adoption of UWB by companies like Apple, Samsung, BMW, and Mercedes-Benz, along with research showing its superiority in secure localization and anti-relay protection.

Looking ahead, the study suggests that UWB systems will be enhanced through integration with AI, biometrics, blockchain, and smartphones, making future vehicle access systems more intelligent, secure, and user-friendly.

Conclusion

Vehicle access systems based on Ultra-Wideband (UWB) technology and secure digital key fobs represent a significant advancement in modern automotive security, authentication, and user convenience. The integration of UWB technology into vehicle access mechanisms addresses many of the limitations associated with conventional Radio Frequency (RF)-based keyless entry systems, particularly vulnerabilities related to relay attacks, signal spoofing, and inaccurate proximity detection. By utilizing precise ranging techniques and Time-of-Flight (ToF) measurements, UWB technology enables highly accurate localization and secure communication between the vehicle and the authorized key fob. This ensures that vehicle access is granted only when the authenticated user is physically present within a predefined secure range, thereby substantially improving protection against unauthorized access attempts. In addition to enhanced security, UWB-based systems provide seamless passive entry functionality, faster authentication, and improved user experience in smart automotive environments. The study demonstrates that UWB technology offers superior reliability, localization accuracy, and operational efficiency when compared to traditional RF-based vehicle access solutions. Furthermore, the growing adoption of UWB by leading automotive manufacturers highlights its increasing importance in the development of next-generation intelligent transportation systems. As the automotive industry continues to evolve toward connected, autonomous, and software-defined vehicles, UWB-enabled secure access systems are expected to become a standard component of future vehicle architectures. The integration of UWB with emerging technologies such as Artificial Intelligence (AI), biometrics, digital smartphones, and intelligent mobility platforms will further enhance vehicle security, automation, and user-centric functionality. Consequently, UWB technology holds strong potential to shape the future of secure and intelligent automotive access systems.

References

[1] “Vehicle Positioning Based on UWB Technology,” Journal of Physics: Conference Series, vol. 1827, no. 1, 2021. [2] “CAN Protocol Based Vehicle Monitoring System,” International Advanced Research Journal in Science, Engineering and Technology (IARJSET), vol. 11, no. 4, 2024. [3] “Mitigating Relay Attacks in Vehicle Access Systems Using BLE and UWB,” Engineering, Technology & Applied Science Research (ETASR), vol. 15, no. 1, 2025. [4] “Bluetooth Based Smart Vehicle Access System,” International Research Journal of Engineering and Technology (IRJET), vol. 8, no. 6, 2021. [5] IEEE, “IEEE Standard for Low-Rate Wireless Networks,” IEEE Std 802.15.4 UWB Communication Standard, 2020. [6] M. Z. Win and R. A. Scholtz, “Ultra-Wide Bandwidth Time-Hopping Spread-Spectrum Impulse Radio for Wireless Multiple-Access Communications,” IEEE Transactions on Communications, vol. 48, no. 4, pp. 679–689, 2000. [7] D. Dardari, A. Conti, U. Ferner, A. Giorgetti, and M. Z. Win, “Ranging With Ultra-Wide Bandwidth Signals in Multipath Environments,” Proceedings of the IEEE, vol. 97, no. 2, pp. 404–426, 2009. [8] F. Zafari, A. Gkelias, and K. K. Leung, “A Survey of Indoor Localization Systems and Technologies,” IEEE Communications Surveys & Tutorials, vol. 21, no. 3, pp. 2568–2599, 2019. [9] J. Decawave, “DWM1000 Ultra-Wideband Transceiver Module Datasheet,” Decawave Technical Documentation, 2020. [10] Bosch Automotive Electronics, “CAN Bus Communication Protocol for Intelligent Automotive Systems,” Bosch Technical White Paper, 2019. [11] Espressif Systems, “ESP32 Series Microcontroller Technical Reference Manual,” Espressif Documentation, 2023. [12] S. Brands and D. Chaum, “Distance-Bounding Protocols,” in Workshop on the Theory and Application of Cryptographic Techniques, Springer, pp. 344–359, 1993. [13] A. Alkhateeb and G. Leus, “Secure Localization and Authentication in UWB-Based Systems,” International Journal of Wireless Information Networks, vol. 27, no. 1, pp. 45–57, 2020. [14] Apple, “Digital Car Key Security Using Ultra-Wideband Technology,” Apple Developer Documentation, 2023. [15] Samsung, “Secure Smartphone-Based Vehicle Access Using UWB and BLE,” Samsung Research Publications, 2022. [16] BMW, “Ultra-Wideband Technology for Secure Passive Vehicle Entry Systems,” BMW Technical Report, 2021. [17] “Secure Smart Key System Using Ultra-Wideband Communication,” International Journal of Automotive Technology, vol. 23, no. 5, pp. 1152–1163, 2022. [18] “Relay Attack Prevention in Keyless Vehicle Entry Systems Using Distance Bounding,” IEEE Access, vol. 9, pp. 102345–102357, 2021. [19] “Implementation of UWB-Based Localization for Intelligent Transportation Systems,” International Conference on Smart Mobility and Communication Technologies, 2023. [20] “Advanced Vehicle Access Control Using Embedded Systems and CAN Communication,” International Journal of Engineering Research and Applications (IJERA), vol. 12, no. 2, pp. 55–61, 2022.

Copyright

Copyright © 2026 Sahaj Sisodiya, Shubha P L, Saniya Sheikh, Sanjana H N. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.