An efficient and safe approach of radar signal capturing and processing : Page 7 of 7

June 04, 2015 //By Peter Aberl, Texas Instruments
On the way to autonomous driving advanced driver assistance systems (ADAS) based on vision, LIDAR and radar have to gradually supersede the driver’s visual sense. To achieve this challenging goal ADAS sensors have to further evolve to become more reliable, more accurate, safer and more efficient. This article focuses on automotive radar and specifically discusses signal processing steps of a modern fast chirp radar system. An example shows how radar signal capturing and processing can be realized in an efficient and safe way. Additional automotive radar aspects like low power, small form factor and scalability are also touched.
The detection of targets and the tracking of objects can be handled by the C66x DSP sub-system. The Cortex-M4s are well suited for configuring the RF components and the AFE5401-Q1, and can administrate and monitor the processing of the other cores. It can also communicate the object information externally. Moreover the TDA3x is equipped with a rich set of peripherals, e.g. video input ports to receive parallel or CSI-2 data from radar front-end, CAN Controllers, various serial interfaces and a QSPI supporting fast quad-lane boot.

The DDR interface can handle various SDRAM types and has an ECC extension for error detection and correction. Internal memories of the TDA3x are also protected with ECC or parity. Besides hardware BIST (built-in self-test for diagnosis of vital parts of the chip) other nifty safety means have been leveraged from Hercules™ TMS570 safety MCU family. This makes TDA3x well suited for safety-critical driver assistance applications like radar. The TDA3xR is available in two package variants, 15mm x 15mm and 12mm x 12mm, whereas the latter is a so-called POP (package-on-package) variant. With the DDR memory on-top of TDA3x the sensor size can be minimized.

Summary and Outlook

The TDA3xR in combination with one or two AFE5401-Q1 devices enables a scalable implementation of short-range, mid-range and long-range radar sensors with 4 to 8 receive channels while software compatibility is maintained. Moreover, the safety features available in TDA3x and AFE5401-Q1 provide a solid foundation for realization of safety critical applications. Both devices are optimized in terms of low power consumption and are available in small packages allowing to shrink the sensor housing. With the POP variant of the TDA3x PCB layout can be simplified and the number of signal layers may be reduced. The performance headroom of the heterogeneous TDA3x architecture permits for example the integration of the AUTOSAR software stack on one of the Cortex-M4s or implementation of sensor fusion for AEB (autonomous emergency brake) in addition to radar signal processing. TDA3xR and AFE5401-Q1 facilitate radar sensor developers to take the next evolutionary step on the way to supersede the driver’s visual sense needed for autonomous driving.

References

TDA3x (www.ti.com/product/tda3)
AFE5401-Q1 (www.ti.com/product/afe5401-q1)


About the author:

Peter Aberl studied electronic engineering with focus on data processing at the Munich University of Applied Sciences. He started to work as Applications Engineer in the area of Automotive Electronics at Texas Instruments (TI) in 1994. Since 2009 he supports TI’s Driver Assistance System-on-Chip and Hercules Safety MCU products at European Automotive customers. He is Senior Member Technical Staff (SMTS) and Principal Field Application Engineer.

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