automotive radar design
TRANSCRIPT
AUTOMOTIVE RADAR DESIGN
DASSAULT SIMULIA - CST STUDIO SUITE
Jim Reed
Senior Engineer for Electromagnetic Applications
CAElynx
310 Depot Street
Ann Arbor MI 48104
Office: (734) 786-3721
Website: www.caelynx.com
TARGET AUDIENCE
2
New to Electromagnetic (EM) Simulation What is 3D EM simulation?
New to CST Studio SuiteWho is CST, and what does their software offer?
New to Automotive Safety DesignHow does EM simulation apply to automotive safety?
New to Frequency Change for Automotive SafetyWhat was the prior band of operation, and what is the new frequency band?
New to the Benefits of the Higher Frequency Operation for Automotive SafetyWhat are the key benefits for the higher frequency operation?
New to the Design Challenges for Higher Frequency OperationHow does the new frequency band create design challenges to current processes?
What are the Manufacturing Challenges for Higher Frequency OperationHow are material science and manufacturing process influenced by new frequencies?
PRESENTATION CONTENT
3
1 Overview Caelynx
2 CST and Dassault
3 CST Studio Suite
4 Benefits of EM Simulation
5Automotive Radar -
The Shift to High Frequency
6 High Frequency PCB Antenna Array
7 Conclusions and Q&A
CAELYNX
NORTH AMERICA / EUROPE
SIMULIA PARTNER
CAELYNX OVERVIEW
5
HQ – Greater Detroit Area / Ann Arbor, MI
North America Satellite Offices
• Philadelphia, PA
• Manchester, NH
• Los, Angeles, CA
• San Jose, CA
• Austin, TX
Europe Satellite Office (Romani and Bulgaria)
• Craiova, Romania
Abaqus, fe-safe, Tosca, Isight,
PowerFlow, Simpack, wave6
CST and Opera
Catia V5, Catia 3DExperience,
Simulia V5, Simulia V6
CAELYNX OVERVIEW
6
Multiple Industry Experience
• Automotive (EV & Battery)
• Consumer Electronics / Interconnects
• Aerospace & Defense
• Medical DevicesDesign Services
Training & Support
Engineering Software
Provides Engineering Design Services,
CAD Software Sales, & CAD Training
CAELYNX OVERVIEW
7
Team of PhD’s, MSc’s, BS’s in Mechanical Engineering, Electrical Engineering , Physics, Thermal
Dynamics, Fluid Mechanics, and Structural Dynamics
Hans Steiner,
Director of Business
Joe Formicola,
President and Founder
CST & DASSAULT
CST & DASSAULT
9
1992 Foundation of CST - Computer Simulation
Technology GmbH, Darmstadt, Germany
Reveal the World We
Live In
1998 CST Microwave Studio Released
2005 CST Studio Suite, Broad Offering of Electromagnetic
and Multiphysics
2016 Acquired by Dassault Systemes - Simulia
CST Studio Suite as All Inclusive Bundle of EM and
Multiphysics Solvers
CST STUDIO SUITE
DC TO LIGHT IN THE EM SPECTRUM
11
Wide Range of Simulation
Techniques, Including:
• 4 General Purpose Solvers
• 20 Application Specific Solvers,
Including Broad Range EM,
Thermal, Mechanical, and Fluid
Dynamics
• Multi-Physics Co-Simulation
• Higher Performance
Computational Features
• Standard Industry
Import/Export, +EDA & Bio...
Static Hz kHz MHz THzGHz
ELECTROMAGNETIC CAPABILITIES
12
Aerospace Applications – EMI / RCS
Antenna Design and Wireless Coupling
Filter Designs
PCB / Package Design - Signal Integrity
Full arbitrary 3D passive electromagnetic (EM) simulation and design using an array of solvers in
CST including time and frequency domain (low and high frequency), eigen, physical optics, etc.
INDUSTRY DESIGN MODULES
13
GPS Helices:
1.6 GHz
TTC &
Horn: 2
GHz
SAR Slotted WG
Array: 9 GHz
Synthesis AssemblyTuning
RF Breakdown
Multipaction
BENEFITS OF
EM SIMULATION
DESIGN
EM SIMULATION DESIGN BENEFITS
15
Improve Product QualityEvaluate a wide field of design space solutions, including Time Domain, Frequency Domain, Thermal, Fluid, Structural, etc.
Enhanced Understanding of Physical DeviceWith EM simulation, engineers can view and study the fields, providing insight, possibly seeing effects that would be difficult to measure.
Reduce RiskEvaluating a design before physical prototype avoids unexpected problems at final stages of product design cycle.
Rapid Virtual PrototypingQuickly generate 3D models that correlate to real world measurements.
Reduce Cost & Time-to-MarketAccurate simulation reduces design and prototyping period, saving costs.
AUTOMOTIVE RADAR
THE SHIFT TO HIGH
FREQUENCY
AUTOMOTIVE RADAR SAFETY FEATURES
17
Radar (Radio Detection and Ranging) is the use of electromagnetic waves to
determine the range, angle, and relative velocity of objects.
It is a key component for the developing automotive safety market, including:
• Blind-Spot Detection (BSD)
• Lane-Change Assist (LCA)
• Front/Rear Cross-Traffic Alert (F/RCTA)
• Autonomous Emergency Braking (AEB)
• Adaptive Cruise Control (ACC)
AUTOMOTIVE RADAR SAFETY
18
The current 24 GHz narrow band spectrum will continue, but the use of the 24 GHz ultra-wide band will be phased out by the year 2022 in both Europe and the U.S. The change in available frequency band is one reason for the industry shift to the 77 GHz band.
21.65 26.65
24 GHz Narrow and Wide Band
76 77 81 GHz
Automotive LRR Band
Automotive SRR Band
FCC 47 CFR 15.253 – Operation within thebands 46.7-46.9 GHz and 76.0-77.0 GHz.
ETSI EN 302 264 – Short-range radar equipmentoperating in the 77 GHz to 81 GHz band.
ETSI EN 301 091 – Radar equipment operating in the 76 GHz to 77 GHz range.
BENEFITS OF RESOLUTION
19
The shift from 24GHz to 77GHz can achieve a 3X performance improvement in velocity
resolution and up to 20x better performance in range resolution, another motivation for the
industry change.
The 76-77 GHz band is available for vehicular long-range radar (LLR) applications, which
allows for high isotropic radiated power (EIRP), applicable for adaptive cruise control.
At 77 GHz, it has a more focused beam, and the wide sweep bandwidth of 77-81 GHz allows
for high resolution for short range radar (SRR).
24 GHz 77 GHz
PHYSICAL APERTURE SIZE REDUCTION
20
The wavelength at 77GHz is roughly one-third that of a 24GHz, so the antenna aperture
for the same gain can be much smaller physically, comparable now to common camera
aperture sizes. This adds placement convenience in the car body.
24 GHz
12mm77 GHz
4mm
HIGH FREQUENCY DESIGN CHALLENGE
21
The smaller wavelength ushers in new challenges in passive microwave component design,
including:
• manufacturing techniques,
• high frequency materials, and
• tolerances in both manufacturing and materials.
In this presentation, a design of a 78 GHz antenna array was optimized in CST Studio Suite
using a high frequency lamination process (Megtron7) to create a quarter waveguide short to
match in a 8 layer board stackup that can be measured with a standard WR12 waveguide.
HIGH FREQUENCY
PCB LAMINATE
DESIGN FOR
ANTENNA ARRAY
HIGH FREQUENCY LAMINATION
23
A realistic 8 layer Megtron7 lamination stackup and process will be used to design a
quarter wavelength vertical waveguide short within the PCB stackup that matches
to a board mount WR12 waveguide adapter.
VERTICAL WAVEGUIDE ADAPTER
24
Etching per layer was utilized to
create a dielectric loaded PCB
waveguide with a perimeter of
ground vias.
Analysis was conducted to
optimize:
• Correct location of the ground
short metal layer,
• PCB waveguide dimensions,
• Coupling stub length on layer 1.
WAVEGUIDE ADAPTER / ANTENNA
25
The port on the mounted waveguide was removed for a radiating aperture and the
return loss of the adapter to radiator compared well across the band.
ANTENNA ARRAY & SCAN ANGLE
26
The array factor for a 5x5 element array at 2.5mm
spacing was calculated for boresight through 25 deg off
boresight. At 25 degrees, pattern integrity degraded.
A board mount waveguide array could be realized
through an injection molded plastic that undergoes a
surface metallization. The benefit of the surface
mount waveguide includes increased gain and reduce
electromagnetic interference with board components.
CONCLUSIONS
27
Overview Caelynx
North America and Europe Simulia / Catia VAR
Dassault and CST Studio SuiteBrief History of CST and Joining Dassault Systemes
CST Studio SuiteBrief Overview of Software Features
Benefits of EM SimulationBrief overview of EM simulation benefits, including insights and costs savings.
Automotive Radar - The Shift to High Frequency• 24 GHz wide band phased out, 77 GHz wide and narrow band adopted• 3X performance in velocity resolution (LRR)• 20X improvement in range resolution (SRR)• Antenna aperture 1/3 the size
High Frequency PCB Antenna ArrayDiscussed a high frequency scanning array example with Megtron7 lamination, configurable for top mount waveguide connector.
THANK YOU
Q & A
Caelynx
Caelynx is a top Simulia Partner in North
America that began in 2005 as a small, three
person automotive FEA house in Ann Arbor,
Michigan, just outside of Detroit. It has
grown over many successful years into a
multi-industry, multi-national, high-end
engineering simulation consultancy and a
leading Simulia software distributor and
support center.
Jim Reed, BS Physics BS Electrical Engineering
Jim Reed is an expert in 3D EM software
modeling with 23 years of microwave design
experience including antennas, RCS, filters,
connectors, impedance matching, PCB, and
RF heating. His employment background
includes aerospace and telecommunication
industries, as well as working directly in
engineering support and training for the 3D
EM simulation software market, both with
Ansys HFSS and CST Microwave Studio.