AUTOMOTIVE RADAR APPLICATIONS

BRANDON RAVENSCROFT

05/01/2015

Motivations

Safety Passive

Does not alter motion of vehicle, i.e. seatbelts Active

Influence motion of vehicle, i.e. accelerate, apply brakes, steer

Comfort Adaptive Cruise Control (ACC)

APPLICATIONS OF RADAR IN AUTOMOTIVE

PCS (Pre-Collision System) ACC (Adaptive Cruise Control) Cross Traffic Alert (CTA) Blind Spot Detection Lane Departure Warning Robotic/Self-Driving Automobiles

A BRIEF HISTORY

Early collision detection units used infrared technology Research in millimeter wave RADAR for automotive

applications began in the early 1970’s First became available in 1998 in the Daimler S class,

originally as ACC only. Widely available by 2003 SiGe semiconductor advances responsible for affordable

application

IMPLEMENTATION

Frequency Modulated Continuous Wave (FMCW) – Typically Linear

Mono-static Modules Located Under Bumpers Multi-Channel: Allows for multiple FMCW signals

WHY 77 GHz?

24 GHz Advantages Cheaper Electronics Power Consumption Noise Figure

77 GHz Advantages Frequency Band Widely

Available in USA, Japan, Europe

Larger Bandwidth Finer Range Resolution Smaller Percentage

Bandwidth Smaller Sensor Aperture

FCC ALLOCATION SPECTRUM

GHz

Amateur

SENSOR CLASSIFICATIONS

Long Range Radar – LRR 55 dBm transmit power

76-77 GHz Band with 600 MHz BW

10 – 250 m Range

Range Resolution: 0.25 m

Narrow Beam Looking Ahead: ACC

Medium Range Radar – MRR -9 dBm/Hz transmit power

77-81 GHz Band with 600 MHz BW

1-100 m Range

Medium Range Radar – MRR (Cont.)

Range Resolution: 0.25 m

Medium Distance: CTA

Short Range Radar – SRR

-9 dBm/Hz transmit power

77-81 GHz Band with 4 GHz BW

15cm – 30m Range

Range Resolution: 3.75 cm

Parking Aid, Close Proximity to Vehicle

RADAR CROSS SECTION

Mazda 6 Mono-static RCS *Image Courtesy of Hasch, et

al.

- Single RCS

- Typically characterized as multiple separate scattering centers

How ACC Works

Linear FM Chirp

Problem: Doppler Frequency𝑓 𝑏=𝑡𝑅𝑇∗𝑘

*Image Courtesy of mathworks

Range is constantly monitored and vehicle speed adjusted accordingly

How ACC Works

Solution: Up Chirp and Down Chirp Averages Out Doppler Shift

𝑓 𝑏=𝑡𝑅𝑇∗𝑘

*Image Courtesy of mathworks

)/2

COMMERCIAL PRODUCTS

MobileEye View 560

Offers CTA and Collision Prevention w/ Visible and Audible Cues

Add to Any Vehocle

TRW AC 1000 79GHz

Long Range – Up To 250m360 Degree SensingIntegrated by Vehicle Manufacturer

REFERENCES "Documentation." Automotive Adaptive Cruise Control Using FMCW

Technology. N.p., n.d. Web. 30 Apr. 2015. <http://www.mathworks.com/help/phased/examples/automotive-adaptive-cruise-control-using-fmcw-technology.html>.

Management, Ntia Office Of Spectrum. U.S. Frequency Allocation Chart (n.d.): n. pag. Web. 30 Apr. 2015. <http://www.ntia.doc.gov/files/ntia/publications/2003-allochrt.pdfhttp://www.ntia.doc.gov/files/ntia/publications/2003-allochrt.pdf>.

Hasch, Jurgen, Eray Topak, Raik Schnabel, Thomas Zwick, Robert Weigel, and Christian Waldschmidt. "Millimeter-Wave Technology for Automotive Radar Sensors in the 77 GHz Frequency Band." IEEE Xplore. IEEE, Mar. 2012. Web. 01 May 2015. <http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6127923>.

REFERENCES "Mobileye 560." Mobileye Mobileye 560 Comments. N.p., n.d. Web. 01

May 2015. <http://www.mobileye.com/products/mobileye-5-series/mobileye-560/>.

"TRW." Radar Technologies. N.p., n.d. Web. 01 May 2015. <http://www.trw.com/electronic_systems/sensor_technologies/radar>.

"Automotive Radar Millimeter-Wave Technology." |Freescale. N.p., n.d. Web. 30 Apr. 2015. <http://www.freescale.com/webapp/sps/site/overview.jsp?code=AUTRMWT>