As autonomous transportation has continued to progress, the role of advanced sensor technologies, particularly radar, has become crucial. Radar systems are vital to environmental perception in autonomous vehicles: they detect targets, range, velocity, and object angles, which are essential for automated braking, avoiding collisions, and lane assistance. Radar systems can accurately measure speed and velocity while detecting objects at great distances, even in unpredictable environmental conditions.
A few more details regarding radar capabilities are worth noting.
Direct speed and velocity measurement – When radar waves reflect off a moving object, Doppler radar uses the Doppler effect to determine the object’s speed and relative motion direction. This applies to vehicles, pedestrians, and cyclists. Radar provides instant velocity data, including direction (toward or away from a vehicle); this real-time speed detection is vital for adaptive cruise control, collision avoidance, and other functions.
Robustness against environmental factors – Radar systems can perform reliably in adverse conditions such as rain, snow, and fog. Unlike cameras, which function poorly in low light or light detection and ranging (LiDAR), which can be disrupted by heavy precipitation, radar operates in the radio frequency spectrum, so it is less affected by visibility constraints. This resilience ensures consistent environmental surveillance for autonomous vehicles, even in unpredictable weather.
High-range detection – Radar systems can enable autonomous vehicles to identify objects several hundred meters away. This extended reach is essential for highway driving, early hazard recognition, and providing ample time for a vehicle to react to distant obstacles. By enabling functions such as emergency braking, lane-keeping assistance, and cross-traffic monitoring, radar enhances safety and improves a vehicle’s ability to navigate complex driving environments.
Radar systems are usually hidden behind autonomous vehicles’ bumper cover or grille for a central, unobstructed view of the road and optimal detection of obstacles while enabling a cleaner, integrated look. This placement optimizes the transmission and reception of reflected signals from nearby surfaces, enhancing accuracy and performance. While general placement is typical, integrating radar systems into vehicles presents numerous design challenges due to potential electromagnetic interference from a variety of sources.
Continental, a leading player in automotive and radar technology, is at the forefront of solving these challenges. By leveraging SIMULIA’s CST Studio Suite, Continental has developed a robust simulation framework to optimize radar integration while reducing costs and enhancing safety and reliability.
The Hurdles of Radar Vehicle Integration
Continental’s autonomous mobility division leverages its expertise in advanced driver-assistance systems (ADAS) to integrate radar sensors seamlessly into vehicle architecture. Though radar technology is powerful, considerable barriers must be addressed. “The performance of an uninstalled radar has ideal characteristics”, explains Radar Vehicle Integration Simulation Engineer Guntaas K. “But when it is integrated [into a vehicle], there are a lot of factors that affect its performance—like the position of the sensor, the shape of the bumper, the thickness of the bumper, and the material.” A well-functioning radar sensor can be rendered ineffective by a poorly designed vehicle component, where interference can result in issues such as signal attenuation, ghost targets, and erroneous target detection.
Signal attenuation is the weakening or loss of signal strength as it travels through a medium, reducing detection range and accuracy. Ghost targets are false or duplicate objects appearing in a radar or sensor system due to signal reflections, multipath effects, or improper filtering, which can lead to errors in object detection. Erroneous target detection is the incorrect identification or misclassification of objects due to interference, noise, or system errors, leading to false positives or negatives in sensing applications.
Radar systems rely on antennas, which typically transmit and receive radio waves and microwaves, making antenna design a key factor. When an antenna design functions optimally, the focus shifts to integrating the sensor into the vehicle. “This process presents additional challenges because the electromagnetic (EM) signals from the sensor interact with surrounding vehicle components like the bumper, chassis, and crash beam,” notes Radar Vehicle Integration Simulation Engineer, Mahima P. These interactions can lead to performance errors, such as direction-of-arrival errors, where a target appears at a different angle than its actual location, or ghost targets. Mahima continues, “To mitigate these issues, we use SIMULIA’s CST Studio Suite technology to determine optimal sensor placement.”
Validation through Measurements
Continental ensures that its simulations align closely with real-world performance by validating results in an anechoic chamber, a room lined with materials that absorb sound or electromagnetic waves to eliminate reflections and simulate a completely open, free-field environment. By conducting controlled experiments, Continental fine-tunes its simulation framework, ensuring that predictions match actual radar behavior within a vehicle. “Compared with other methods, simulation performs well,” explains Mahima.
The adoption of CST Studio Suite for electromagnetic simulation in radar vehicle integration has led to significant efficiency gains. Measurements alone require huge amounts of time. Mahima continues, “Simulation just takes a day, whereas altering physical setups and redoing measurements takes weeks.” Additionally, simulations have contributed to significant cost reductions: “We don’t have exact numbers, but simulations have reduced costs by approximately 30 to 40 percent,” notes Guntaas, emphasizing the economic benefits of virtual testing over physical prototyping.
The ability to simulate various configurations before manufacturing enables Continental to detect potential design flaws early in the development process and reduce the likelihood of expensive errors downstream. “When a radar is placed behind a bumper, many factors affect its performance, such as sensor positioning, tilt, and nearby metal parts that contribute to reflections,” explains Guntaas. “With simulation, we can analyze these variables efficiently.”
For example, if a customer wants to adjust the sensor position by 1mm or 2mm, change the bumper’s thickness, or switch materials, Continental engineers can evaluate the impact without the high cost of physical testing. Guntaas continues, “This allows us to quickly recommend the optimal sensor placement, bumper thickness, and material to ensure the best radar performance for original equipment manufacturers.”
The Importance of Using the Right Tools
Continental especially appreciates and relies on CST Studio Suite for its accuracy and speed. “We found that SIMULIA’s tools closely align with actual measurements, making them a reliable and trusted solution,” observes Mahima. The software’s various solvers, such as the T-solver for high-accuracy simulations and the A-solver for large-scale models, offer options. “This flexibility in solvers makes it stand out,” she adds.
Beyond accuracy, CST Studio Suite is user-friendly and is backed by strong technical support. “We get really good technical support from the CST team,” Mahima states. “They resolve our queries with high priority and even connect us with their R&D team when needed.” This collaboration ensures that Continental engineers can push the boundaries of radar integration while maintaining high confidence in their results.
Future Directions
As self-driving technology advances, radar integration will become increasingly critical. A future with satellite-based radars offering 360-degree coverage could reduce reliance on vehicle-mounted sensors. “Satellite radars would enable comprehensive detection in all directions—front, back, and sides—marking a major leap forward in radar technology,” enthuses Guntaas. While fully autonomous vehicles are still a few years away, simulation-driven design is helping to rapidly advance their development.
Continental’s approach to radar vehicle integration showcases how simulation can drive innovation in autonomous mobility. By leveraging SIMULIA’s CST Studio Suite software, the company has optimized radar placement, reduced costs, and ultimately enhanced safety in self-driving vehicles. The success of these simulations highlights the growing role of virtual testing in automotive engineering, paving the way for safer and more efficient autonomous transportation.
Interested in the latest in simulation? Looking for advice and best practices? Want to discuss simulation with fellow users and Dassault Systèmes experts? The SIMULIA Community is the place to find the latest resources for SIMULIA software and to collaborate with other users. The key that unlocks the door of innovative thinking and knowledge building, the SIMULIA Community provides you with the tools you need to expand your knowledge, whenever and wherever.
Katie is the Editor of the SIMULIA blog, an expert in engineering and scientific communication, and a strategic digital marketer. Katie has a BA in English and Writing from the University of Rhode Island and a MS in Technical Communication from Northeastern University. She is also a proud SIMULIA advocate, passionate about democratizing simulation for all audiences. Katie is a native Rhode Islander who lives just outside of her favorite city, Providence. She is a true New Englander and loves sharing all the cool things NE has to offer. She enjoys a variety of hobbies including history, astronomy, science/technology, science fiction, true crime, fashion and anything associated with nature and the outdoors. She is also mom to a 5-year old budding engineer and two crazy rescue pups.