Radar technology is changing three major trends in the cockpit sensing market

Radar sensors not only change the way vehicles sense their surroundings, but also how they sense objects and occupants. Picture this: a car that can detect a child forgotten in the back seat or a sick driver and design a system to take action to mitigate the situation.

Radar’s ability to detect through solid materials allows it to detect unattended children, monitor occupant status and estimate driver vital signs more accurately than ever before.

In this technical article, I will explore three trends in the automotive in-cabin perception market as more and more automakers turn their attention to radar sensors.

Trend 1: Functions beyond child presence detection

To comply with regulatory bodies such as the European New Car Assessment Programme, automakers are turning to radar sensors for child presence detection. But they found they didn't have to stop there.

Radar's increasing capabilities for in-cabin sensing improve the accuracy of systems such as seat belt reminders and airbag deployment and better serve vehicle occupants. Heavy objects placed on the seat will no longer trigger the seat belt reminder. When a child is in the car, the airbags deploy at different speeds, reducing the risk of a crash.

Radar sensors can also accurately detect a driver's drowsiness or an occupant's breathing and heart rate. The vehicle can then use this information to identify anomalies. Once alerted, the driver can take appropriate measures, such as taking a break after driving for a while or parking in the event of a physical condition.

Trend 2: Using 60 GHz radar sensors for in-cockpit sensing

Automotive Tier 1 suppliers have explored different operating frequency bands for radar in-cabin sensing applications. For example, 24 Ghz radar sensors are not suitable for these applications because their poor range and speed resolution do not provide accurate results. The large sensor size makes vehicle integration very difficult. Finally, UWB at 24 Ghz will not be available for automotive applications after 2022 due to mandates from the US Federal Communications Commission and the European Telecommunications Standards Institute.

For more accurate detection of velocity and angular resolution, it is better to use higher frequencies such as 60 GHz or 77 Ghz. Depending on the region, in-cabin sensing applications can use 60 or 77 Ghz sensors. Most regions are selecting 60 Ghz sensors, but Tier 1 suppliers should work with regulators in the region for further clarification.

Texas Instruments offers a scalable radar portfolio with TI millimeter wave sensors in the 60-GHz (AWR6843) and 77-GHz (AWR1843) frequency bands. These single-chip devices are pin-to-pin and software-compatible—features that allow designers to build sensors for deployment in different regions because they can be built on a common printed circuit board (except for antenna adjustments) and developed in both Algorithms and software that can run on every platform.

Trend 3: Adjustable sensor architecture for any size vehicle

The integration of sensors within a vehicle affects its design (form, antenna) and functionality. Because radar can penetrate solid materials such as plastics and fabrics, automotive designers can place radar sensors in many different locations within the vehicle.

When the sensor is integrated into the roof canopy facing the center of a dual-cab vehicle, a single radar sensor such as the (AWR6843) can detect a child in a rear-facing child seat or standing in a footwell and can detect Detection and classification of other occupants throughout the car. This is possible thanks to the on-chip processing and storage capabilities of the AWR6843 chipset. The integrated digital signal processor and microcontroller on the AWR6843 enable complex algorithms and communication to the car. Open Systems Architecture Stack (AUTOSAR).

In large three-row vehicles, two AWR6843 sensors detect all occupants. Because the AWR6843 features two Controller Area Networks (CANs) with flexible data rate interfaces, the two sensors can easily synchronize and communicate with the vehicle's CAN network, making the solution scalable to any size and any seat count. car.

The sensor can also be placed in the overhead console or B-pillar, which can be a challenge with the size of the sensor. TI radars enable small form factor sensors that facilitate easy vehicle integration.

TI's scalable portfolio of radar sensors includes single-chip and imaging radar chipsets. With cross-device compatible software, portability is easier than ever, allowing you to start designing your next in-cockpit perception system today.