Driver and occupant monitoring will be a significant growth market for semiconductor manufacturers in the next five years. S&P Global Mobility forecasts that in-cabin monitoring leveraging cameras and radars will represent an opportunity of $908 million in 2029, up from $93 million in 20221, representing a 38 percent compound annual growth rate during this period. To support this growth, radar sensors are being deployed across a rapidly expanding range of automotive applications, tapping into new and emerging opportunities for automakers.
In the automotive market, radar is widely deployed in mid- and long-range sensing solutions for advanced driver assistance systems and automated safety features. These include automated emergency braking, adaptive cruise control and blind spot detection, leveraging frequencies between 76 to 81 GHz. As radar solution providers look to deploy frequencies in the terahertz spectrum, this will unlock higher resolution and greater precision in-cabin sensing to complement camera-based solutions for challenging driver and occupant monitoring systems (DMS/OMS) applications such as vital signs detection (VSD).
indie Semiconductor is a “pure-play” automotive system-on-chip (SoC) specialist. We offer the world’s first commercial fully integrated 240 GHz radar front-end (RFE) SoC transceiver. Operating at 240 GHz, which is significantly higher than traditional automotive radar systems, the TRA_240_091 offers automakers a radar solution with high resolution, enhanced detection and robust performance.
PRODUCT DESIGN
The cascadable RFE of the TRA_240_091 combines a 240 GHz operating frequency with a bandwidth of up to 45 GHz, assembled in a low-cost QFN package. Developed for applications within the license-free 244 to 246 GHz ISM band and beyond, the SoC can operate as a single-channel transceiver with an on-chip or off-chip voltage-controlled oscillator (VCO) or in an array with many devices synchronized. The maximum range can reach several meters, depending on the aperture of the lens placed on top of the chip.
The silicon-based solution includes a VCO, divide-by-8 frequency divider, SPDT switch, frequency multiplier-by-9 chain, frequency doublers, mixers, low noise amplifier, power amplifier, antenna/coupler and integrated antenna, as shown in Figure 1. Theoretically, operation at 240 GHz equates to a measurement accuracy of 1.25 mm in free space; the 45 GHz of supported bandwidth gives a radar range resolution down to 6 mm in air and improves for materials with a refractive index higher than one. This is because the range resolution is inversely proportional to the material’s refractive index.
Figure 1 TRA_240_091 functional block diagram.
EVOLVING AUTOMOTIVE RADAR APPLICATIONS
Leveraging higher frequencies (120 to 140 GHz), radar technology is quickly finding new use cases and opportunities for automotive applications, including DMS/OMS applications such as VSD. VSD offers a non-invasive and continuous method to monitor an occupant’s physiological parameters, such as heart or respiration rates. With radar-based in-cabin sensing, the vehicle can monitor characteristics of driver alertness, like drowsiness or a dramatic increase in heart rate. It can also monitor passenger presence, such as a sleeping infant in the rear seat or distracted/drowsy driving and initiate critical safety responses and alerts that can reduce the chance of injury to occupants or accidents to other road users. The TRA_240_091 is also designed to support driver convenience features such as gesture control, providing carmakers with implementation, privacy and application capability options relative to camera-based solutions.
As an integrated transceiver circuit with an on-chip antenna, the TRA_240_091 eliminates the need for external antennas. This significantly simplifies application development, streamlines printed circuit board design and minimizes form factor size and cost. This is particularly important in applications where external antennas impose design limitations that are unacceptable to automotive manufacturers and consumers who want sleek vehicle interiors.
The superior precision of 240 GHz radar also supports new and rapidly emerging vehicle dynamics and monitoring applications. Initial use cases are expected to include assessing and controlling air spring-based suspension settings for trucks and other heavy vehicles, providing a lower-cost, higher-accuracy alternative to mechanical systems. Radar systems at 240 GHz can also support fine-grade monitoring of gas tank levels and real-time road surface quality and hazard assessments, leading to dynamically adapted ride quality.
INDUSTRIAL-SENSING APPLICATIONS
While automotive applications present a huge opportunity, indie’s 240 GHz solution can also readily address adjacent industrial terahertz frequency applications, which Mordor Intelligence estimates will be a $1.8 billion opportunity by 2028.2 The TRA_240_091 architecture means that it is also well suited to a wide array of industrial-sensing use cases, including thickness measurement of non-conductive material, non-destructive material analysis, imaging, in-line inspection and level metering. The exceptionally high resolution and bandwidth benefits of 240 GHz radar also support end-of-line product quality applications, tank-level monitoring, surface inspections and security scanners.
The analog RFE chip can be used as a standalone front-end in applications such as vibration measurement, which integrates easily with AI-based processing. This approach helps identify unexpected patterns and predict maintenance issues before they happen. This device also provides the flexibility to scale up to massive MIMO arrays for imaging and scanning applications, all using the same component.
CONCLUSION
Radar technology for existing and emerging automotive- and industrial-sensing use cases brings unique versatility and robustness to the market. Through detection performance, high-resolution capabilities and the ability to operate in low-visibility weather conditions, radar enables enhanced safety features, vehicle efficiency and cost and miniaturization, creating affordable solutions for automakers.
The TRA_240_091 seamlessly integrates into indie Semiconductor’s multi-modal portfolio, which includes LiDAR, ultrasonic sensors and camera systems. This multi-modal approach ensures that vehicles equipped with indie sensors have robust sensing capabilities, providing a more holistic view of the environment and enhancing overall safety and performance. indie Semiconductor has set a new standard for the industry to achieve greater heights in automotive and industrial safety and automation.
References
- “Automotive Semiconductor Market Tracker – March 2024,” S&P Global Mobility, April 1, 2024, Web: autotechinsight.ihsmarkit.com/shop/product/5003493/automotive-semiconductor-market-tracker-march-2024.
- ”Terahertz Technology Market Size & Share Analysis - Growth Trends & Forecasts (2024-2029),” Mordor Intelligence, Web: mordorintelligence.com/industry-
reports/terahertz-technologies-market.
indie Semiconductor
Aliso Viejo, Calif.
www.indiesemi.com/