Despite the effects of the automotive chip shortage on new vehicle production, the industry is forecasted to develop 15.5 million units in 2022, according to IHS Markit. Between increased electrification, the continual addition of sensors, and the more onboard data, today’s cars look nearly unrecognizable from models even 10 years ago. 

Behind this change is a slew of hardware from semiconductor companies making big pushes at the circuit level. Today, Texas Instruments is aiming to progress advanced driver assistance systems (ADAS) with the release of its new radar sensor SoC. 

Example block diagram of an advanced driver assistance system. Image used courtesy of Avnet

All About Circuits had the chance to talk with Yariv Raveh, TI's manager of the radar sensors business unit, to hear about this new device first hand. 

Sensors Stack Up in Automotive Design

ADAS is no longer a feature reserved for luxury vehicles. Today’s ADAS systems, targeted at Level 2 autonomy and higher, appear in most commercial cars and consist of many different sensors. The most advanced autonomous vehicles, however, combine radar, LiDAR, and cameras—each offering a different range, field of view, and resolution. This provides more comprehensive vision coverage around a vehicle. 

TI noted that to keep up with ADAS advances, OEMs are ramping up the number of sensors per car—amounting to over 70 sensors in a modern vehicle. 

Today’s ADAS systems consist of many different sensors for different ranges and field-of-view. Image used courtesy of Texas Instruments

Packing this number of sensors in a car brings a plethora of design challenges. One of these challenges is handling the enormous amounts of data created and communicated throughout the vehicle. Another challenge is area and weight: where do OEMs put all of these sensors in a space-constrained vehicle? 

“We are finding that real estate is becoming a real pain for the OEMs,” Raveh explains. “They are now dealing with things like figuring out where to locate the sensors without jeopardizing other functions or without too many complexities.”

TI Introduces New mmWave Radar Sensor

To address these sensor complexities, Texas Instruments has announced the AWR2944, the company's second-generation high-performance automotive SoC for corner and long-range radar. 

“Traditional automotive radar sensors are based on discrete radar subsystems, largely consisting of the radar itself and the processing unit,” Raveh prefaces. But with this new family of 77-GHz radar SoCs, TI is instead integrating both of these subsystems onto a single chip.

The AWR2944 offers a 30% reduction in size compared to traditional sensors—saving on BOM, area, and weight; the mmWave radar sensor is about the size of a coin.

A block diagram of the AWR2944. Image used courtesy of Texas Instruments

Beyond this, the AWR2944 has made significant performance improvements from its predecessor, the AWR2243. 

Raveh notes, “With the AWR2944, we are adding one more transmitter to the device, an improved radio subsystem, and more advanced computing resources.” In addition, the second-gen SoC is introducing support for Ethernet communication—a feature that is becoming increasingly crucial as data volume and traffic increases in-vehicle.

Altogether, some of the important hardware offerings include 4 Rx and Tx channels, a radar pre-processing hardware accelerator block, 4 MB of on-chip memory, and a built-in calibration and monitoring engine. Thanks to these improvements, TI says the AWR2944 allows for a 33% higher radar resolution and a 40% increase in radar range compared to other solutions on the market. The increased radar range is attributed to Doppler division multiple access (DDMA)-based signal processing, which increases the SoC's ability to detect oncoming vehicles from further away. 

ADAS data communication system. Image used courtesy of Texas Instruments

These resolution improvements allow the chip to not only detect obstacles but also to note the difference between pedestrians and other cars. 

Higher Integration Sophisticates ADAS

When it comes to in-vehicle sensors, more doesn't always mean better. In fact, the trend toward more onboard sensors in automobiles could come at the price of an increased area, lower performance, and higher cost. With the new AWR2944, Texas Instruments hopes to help OEMs and Tier 1s avoid sensor tradeoffs by offering more integrated solutions at reasonable price points.

TI believes its highly-integrated solution can help drivers detect objects more quickly, keep an eye on blind spots, and safely switch lanes and turn corners to decrease accidents. Its “sensor fusion” technology, combined with an integrated DSP, allows the mmWave radar sensor to run ML algorithms for object classification on-chip.  

TI's AWR2944 radar sensor is part of a broader ADAS portfolio that includes AI processors, PMICs, and multi-rail PMICs for radar monolithic microwave processors.