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 77 GHz Advantages Cheaper Electronics Power Consumption Noise Figure 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 - Single RCS Typically characterized as multiple separate scattering centers Mazda 6 Mono-static RCS *Image Courtesy of Hasch, et al.

How ACC Works 𝑓 𝑏 = 𝑡 𝑅𝑇 ∗𝑘 Linear FM Chirp Problem: Doppler Frequency 𝑓 𝑏 = 𝑡 𝑅𝑇 ∗𝑘 Problem: Doppler Frequency 𝑓 𝑏 + 𝑓 𝑑 Range is constantly monitored and vehicle speed adjusted accordingly *Image Courtesy of mathworks

How ACC Works 𝑓 𝑏 =(𝑓 𝑏𝑢 + 𝑓 𝑏𝑑 )/2 𝑓 𝑏 = 𝑡 𝑅𝑇 ∗𝑘 Solution: Up Chirp and Down Chirp Averages Out Doppler Shift 𝑓 𝑏 =(𝑓 𝑏𝑢 + 𝑓 𝑏𝑑 )/2 𝑓 𝑏 = 𝑡 𝑅𝑇 ∗𝑘 *Image Courtesy of mathworks

COMMERCIAL PRODUCTS TRW AC 1000 79GHz Long Range – Up To 250m 360 Degree Sensing Integrated by Vehicle Manufacturer MobileEye View 560 Offers CTA and Collision Prevention w/ Visible and Audible Cues Add to Any Vehocle

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>