Texas Instruments Millimeter-Wave Radar Sensors Enhance Automotive Safety

More and more mid-range and even low-cost vehicles are now being equipped with advanced driver-assistance systems (ADAS), reflecting the growing consensus around the concept of technology democratization. A safe and reliable ADAS experience for drivers and passengers relies on robust underlying electronic systems, and sensors play a critical role in bridging the vehicle with its surrounding environment.

Millimeter-Wave Radar Enhances Driving Safety Inside and Out

To ensure safe driving, various sensors must work together, and millimeter-wave (mmWave) radar is a relatively new yet increasingly important technology. Like image sensors, mmWave radar can detect external environmental data and is used in applications such as front radar, corner radar, and imaging radar. It can also work in tandem with cameras for sensor fusion, offering more reliable perception data.

Beyond external sensing, mmWave radar is also capable of monitoring the interior of vehicles, contributing to enhanced passenger safety. Use cases include in-cabin child presence detection (CPD), occupant detection/positioning and classification, and intrusion detection—providing a high level of safety and reliability.

Single-Chip mmWave Radar Simplifies System Design

Millimeter-wave radar typically operates in the 10 GHz to 200 GHz frequency range, with automotive applications concentrated in three frequency bands: 24 GHz, 60 GHz, and 77 GHz. Higher frequency bands offer finer detection capabilities due to shorter wavelengths but also come with higher design complexity. Currently, 77 GHz is widely used for exterior vehicle applications, while 60 GHz dominates in-cabin radar—though the 60 GHz band still lacks a unified global standard and requires regulatory cooperation for deployment.

Compared to image sensors, mmWave radar offers several advantages:

• It penetrates non-metallic objects like plastic, clothing, and glass.

• It performs reliably in fog, rain, snow, and poor or glaring lighting conditions.

• It can detect vital signs such as breathing and heartbeats.

• It ensures privacy as it does not store image data.

Traditionally, radar systems required multiple discrete chips, resulting in bulky, power-hungry, and costly designs. Today, suppliers use RF-CMOS processes to integrate RF transceivers, PLLs, analog/digital signal chains, and digital processing blocks into a single chip. However, many solutions still require an external MCU or DSP to process radar data. Texas Instruments (TI) leads the way by integrating all radar subsystems into a single chip, reducing system size by 50% and lowering cost and development complexity.

CPD Function: Ensuring Child Safety

Child Presence Detection (CPD) has become a key in-cabin safety feature. It demonstrates mmWave radar’s advantages: precision, privacy, and flexible deployment.

According to U.S. data, from 1990 to 2023, 1,083 children died from heatstroke after being left in vehicles—averaging 40 deaths per year in the last five years. Over half of these were caused unknowingly by caregivers. In response, global standards are evolving to require CPD. For instance, the EU has mandated CPD as part of the Euro NCAP 2025 requirements for the highest safety ratings. Similar legislation is expected in the U.S. and China.

CPD systems typically consist of detection and alert mechanisms. Detection can be direct (e.g., identifying breathing, heartbeat, motion) or indirect (e.g., door status, seat pressure, capacitance). Alerts can be sent via mobile notifications or in-vehicle warnings.

While indirect detection offers high accuracy and easy installation, it may produce false alarms or miss non-seat occupants. Direct detection methods—cameras, UWB, and mmWave radar—are more reliable. Importantly, only direct sensing solutions will count toward Euro NCAP safety scores starting in 2025, with extended coverage requirements (e.g., footwells, trunks).

Why mmWave Is the Optimal CPD Technology

Cameras pose privacy and lighting challenges, making them less suitable for CPD. UWB is limited to CPD alone and requires additional sensors for other functions. In contrast, mmWave radar supports multiple functions—CPD, intrusion detection, and occupancy sensing—with a single chip.

Furthermore, mmWave radar chips typically cost about 80% of UWB solutions, offering lower system costs and simplified development. This makes mmWave a superior option for automakers.

Flagship Product: AWRL6844 mmWave Radar Sensor

TI’s AWRL6844 is a next-generation mmWave radar sensor that runs edge AI algorithms on a single chip. It supports occupant detection for seatbelt reminders, child presence detection, and intrusion detection—enhancing in-vehicle safety.

The AWRL6844 includes a high-performance RF front end with 4 transmitters and 4 receivers, forming 16 virtual channels for high spatial resolution. The optimized cost structure makes it attractive for OEMs.

Processing-wise, the chip integrates:

• Arm R5F core with dual-precision FPU (200 MHz)

• HWA 1.2 accelerator for FFT/log-magnitude/CFAR (200 MHz)

• C66x DSP for radar post-processing (450 MHz)

• 2.5 MB on-chip RAM

This heterogeneous multi-core architecture enables AI deployment for tasks like accurate passenger detection and position tracking. For CPD, a hybrid method uses traditional radar processing for feature extraction and AI models for distinguishing between adults and children—achieving over 90% classification accuracy and reducing deployment time.

In intrusion detection, the AI capabilities filter out noise from vehicle motion or external activity, reducing false alarms and improving user experience.

Enhanced Functional and Cybersecurity

Automotive features are increasingly vulnerable to cyber threats due to higher connectivity. Ensuring secure system nodes is vital. The AWRL6844 meets ASIL-B safety standards and includes an embedded hardware security module (HSM) for secure boot, key management, and encryption. It supports various encryption algorithms, including Chinese SM2, SM3, and SM4, and is compliant with ISO 21434 cybersecurity standards.

TI’s Complete mmWave Radar Portfolio

Texas Instruments offers a comprehensive portfolio covering high-performance front-ends to ultra-high-resolution, low-power single-chip radars. Applications range from external parking assistance, corner radar, forward radar, and 4D imaging radar, to in-cabin uses such as intrusion detection, CPD, seatbelt reminders, gesture recognition, and door sensing—each optimized for its respective use case.

Advanced Packaging Technologies

Traditional radar modules mount antennas directly on the PCB, which can limit layout flexibility and increase manufacturing complexity. To overcome these challenges, TI has developed two proprietary packaging technologies:

• Antenna-on-Package (AoP): This approach integrates the antenna elements directly into the package substrate. It simplifies PCB design and reduces signal loss due to shorter signal paths between the RF circuitry and antennas. AoP enables high performance while maintaining a compact footprint.

• Antenna-in-Package (LoP): With this technology, antennas are embedded within the chip package itself. LoP delivers an even more compact and robust design, providing better environmental protection and reducing system size. It is especially well-suited for in-cabin applications where space is at a premium.

These innovations allow designers to build radar modules that are smaller, lighter, and easier to integrate into a wide range of automotive environments.

Closing Thoughts

Millimeter-wave radar technology is rapidly becoming a cornerstone of automotive safety, enabling both exterior and in-cabin sensing capabilities. Its ability to function reliably in challenging environmental conditions, respect user privacy, and detect subtle biometric signals like breathing and heartbeats makes it uniquely suitable for modern ADAS and safety features.

Texas Instruments continues to lead the industry with highly integrated, single-chip mmWave radar sensors that simplify design, reduce cost, and enhance performance. From child presence detection to intrusion monitoring, TI’s radar portfolio supports a safer and smarter driving experience.

As regulatory bodies increasingly mandate safety features like CPD and intrusion detection, mmWave radar’s role in ensuring vehicle and passenger safety will only grow—paving the way for a new era of intelligent, secure, and human-centric mobility.