System for radio-based detection of traffic light phases and remaining run times for autonomous and semi-autonomous vehicles

Abstract

System for detecting traffic light phases for autonomous and semi-autonomous vehicles, comprising a radio transmitter arranged on a traffic light system, which emits a fixed radio frequency in the MHz range for each signal phase, and a radio receiver integrated in the vehicle, which is configured to selectively detect the emitted frequencies and to determine the current signal phase of the traffic light system from them.

Description

1. Purpose of the invention

[0001] The purpose of the invention is to provide a simple, robust, and cost-effective system for the wireless transmission of traffic light phases and their remaining durations to vehicles. The system enables precise, weather-independent, and low-latency detection of the current signal phase, as well as a predictive driving strategy to optimize safety, traffic flow, and energy efficiency. 2. Technical problem

[0002] Modern autonomous and semi-autonomous vehicles rely on reliable information about traffic light phases. Existing solutions are predominantly based on: • camera-based detection (susceptible to interference in rain, snow, fog, backlighting) • complex digital V2X protocols (high costs, infrastructure requirements, latency) • cloud-based systems (dependence on network coverage)

[0003] These technologies are expensive, prone to errors, and require extensive infrastructure. What's needed is a simple, local, robust, and immediately deployable system that doesn't rely on complex communication technologies.

[0004] By combining GPS position data, a digital library of recorded traffic light locations and speed limits, and the received radio frequencies from the traffic signal system, the vehicle can detect the traffic light significantly earlier than with purely camera-based systems and reliably determine the signal phase. This completely eliminates the typical disadvantages of camera-based systems, such as late detection, obstructions to visibility, or weather-related failures. 3. Solution approach of the invention

[0005] The invention proposes a system in which each traffic light has a transmitter that emits precisely defined radio frequencies in the MHz range. Each frequency uniquely corresponds to a traffic light phase (red, yellow, green). Additionally, the remaining duration of the current phase is transmitted via a simple signal format.

[0006] Vehicles have a corresponding receiver that selectively filters the relevant frequencies, recognizes the current traffic light phase, evaluates the remaining duration of the phase, and derives an optimal driving strategy from this.

[0007] The combination of GPS tracking, a database of traffic light positions and speed limits stored in the vehicle, and the traffic light system's transmitted frequency signals enables particularly early, reliable, and weather-independent detection of the traffic light and its signal phase. This leads to significantly more anticipatory driving behavior, increased energy efficiency, and a substantial improvement in road safety. Optionally, a central transmitter can collect information from multiple traffic lights and broadcast it over a wide area. 3.1 Mechanical Module • Compact transmitter housings for mounting on existing traffic light poles • Vibration and weather-resistant design • Antenna module with defined radiation pattern • Optional: modular brackets for retrofitting to older traffic light systems 3.2 Electrical Module • Low-energy radio module in the MHz range • Microcontroller for controlling frequency switching • Timer unit for generating the remaining runtime signals • Power supply via existing traffic light circuits • Vehicle-side receiver with bandpass filters and signal decoder 4. Functionality and advantages

[0008] The system enables: • Reliable detection of the traffic light phase regardless of visibility conditions • Transmission of the remaining time (e.g. “Red light 7 seconds remaining”) • predictive speed control • Reduction of abrupt braking maneuvers • Energy savings through optimized acceleration and deceleration • Increased safety at intersections • Easy integration into existing vehicle electronics 5. Compatibility with standard products

[0009] The invention is compatible with: • all existing traffic light systems (retrofit capability) • autonomous and semi-autonomous vehicles • GPS-based navigation systems • Standard vehicle control units (ECUs) • existing V2X systems (as a supplement, not as a replacement)

[0010] Since the system is based on simple radio frequencies, no proprietary protocols or expensive communication modules are required. 6. Summary of the advantages • extremely low costs • High robustness • immediate responsiveness • No dependency on the internet or cloud • easy retrofitting • global scalability • Increased road safety • optimized traffic flow • Energy and emission reduction 7. State of the art and comparison

[0011] The state of the art includes: • Camera-based traffic light recognition • LiDAR-based detection • digital V2X communication (ITS-G5, C-V2X) • Cloud-based traffic light information

[0012] These systems are: • expensive • complex • prone to malfunctions • depending on network coverage • difficult to retrofit 7.1 Comparison to the state of the art / today

[0013] In contrast, the present invention offers: • Analog, frequency-based transmission instead of digital protocols • Local direct communication instead of cloud dependency • minimal hardware requirements • No latency issues • No line-of-sight dependency

[0014] This invention thus represents a completely new, simplified and robust alternative. 8. Degree of innovation

[0015] The invention is innovative because: • it encodes traffic light phases via pure radio frequencies • it also transfers the remaining time period • it manages without digital protocols • it enables ultra-light V2I communication • it does not replace existing systems, but complements and improves them

[0016] This combination is not known in the prior art. 9. Ergonomic and sustainable properties of the invention • Reduction of abrupt braking → more comfortable driving experience • Optimized speed → lower energy consumption • Less stop-and-go traffic → lower emissions • Easy retrofitting → sustainable use of existing infrastructure • Low material usage → low ecological footprint • Increased safety → fewer accidents and stressful situations

Images