Radar for Fully Autonomous Driving (Artech House Radar Library)

This is the first book to bring together the increasingly complex radar automotive technologies and tools being explored and utilized in the development of fully autonomous vehicles - technologies and tools now understood to be an essential need for the field to fully mature. The book presents state-of-the-art knowledge as shared by the best and brightest experts working in the automotive radar industry today -- leaders who have "been there and done that." Each chapter is written as a standalone master class with the authors, seeing the topic through their eyes and experiences. Where beneficial, the chapters reference one another but can otherwise be read in any order desired, making the book an excellent go-to reference for a particular topic or review you need to understand. You'll get a big-picture tour of the key radar needs for fully autonomous vehicles, and grasp the complications and challenges that need to be addressed, including weather impacts, integration and safety issues, and RFI interference as the number of vehicles with radars continues to grow. This is an essential reference for engineers currently in the autonomous vehicle arena and/or working in automotive radar development, as well as engineers and leaders in adjacent radar fields needing to stay abreast of the rapid developments in this exciting and dynamic field of research and development. Radar for Fully Autonomous Driving Contents Part I: Radar Technologies for Autonomous Vehicles Chapter 1 Modern Radar Sensors in Advanced Automotive Architectures 1.1 Inspiration for More Advanced Systems 1.1.1 Traffic Density and Fatal Accident Rate 1.1.2 Human Factor 1.1.3 Autonomous Driving Levels 1.2 The Evolving Automotive Radar Landscape 1.3 Fast Chirp Sequence Radar Sensing 1.4 RFCMOS Car Radar Transceiver 1.5 Elements of a Radar Module 1.6 Angular Resolution Increase: MIMO Example and Cascaded Application 1.7 Vehicle Network and Compute Considerations 1.7.1 Vehicle Network Architecture Evolution 1.7.2 Distributed Versus Centralized Processing 1.7.3 Conclusion 1.8 Summary 1.9 Acknowledgments References Chapter 2 Design Considerations for Automotive Radar 2.1 Radar Requirements 2.2 The Spectrum for Automotive Radar 2.3 Range (Distance) Required for Automotive Radar 2.4 Automotive Radar Installation 2.5 Automotive Radar Considerations for Scanning the FOV 2.6 Frequency Modulation Waveforms and the Radar Data Cube 2.7 Outputs from Automotive Radar References Chapter 3 Digital Code Modulation 3.1 Introduction 3.2 FCM Versus DCM Architecture 3.3 Basics of DCM Radar 3.3.1 Range Processing 3.3.2 Velocity Processing 3.3.3 Angle Processing 3.4 DCM Radar Attributes 3.4.1 High Contrast Distance: Matched Filter 3.4.2 High Contrast Resolution 3.4.3 CDM MIMO (Higher Power on Target) 3.4.4 Interference Robustness and Interference Mitigation 3.4.5 Cascading: Coherent and Quasi-coherent Sensors and Networks 3.4.6 Code Design 3.5 DCM Radar Implementation References Chapter 4 Automotive MIMO Radar 4.1 Virtual Array Synthesis via MIMO Radar 4.2 Waveform Orthogonality Strategies in Automotive MIMO Radar 4.2.1 Waveform Orthogonality via TDM 4.2.2 Waveform Orthogonality via DDM 4.2.3 Waveform Orthogonality via FDM 4.3 Angle Finding in Automotive MIMO Radar 4.3.1 High Resolution Angle Finding with ULA 4.3.2 High Resolution Angle Finding with SLA 4.4 High Resolution Imaging Radar for Autonomous Driving 4.4.1 Cascade of Multiple Radar Transceivers 4.4.2 Examples of Cascaded Imaging Radars 4.4.3 Design Challenges of Imaging Radar 4.5 Challenges in Automotive MIMO Radar 4.5.1 Angle Finding in the Presence of Multipath Reflections 4.5.2 Waveform Orthogonality in Automotive MIMO Radar 4.5.3 Efficient, High Resolution Angle Finding Algorithms Are Needed References Chapter 5 Synthetic Aperture Radar for Automotive Applications 5.1 Introduction 5.1.1 Historical Background 5.1.2 Comparison to Traditional Radar Systems 5.1.3 SAR and Point Cloud Imaging Performance 5.1.4 Applications for Automotive Use 5.2 Mathematical Foundation 5.2.1 Key Assumptions 5.2.2 Signal Model 5.2.3 Slow Time 5.3 Building an Automotive SAR 5.3.1 Measuring Ego-Motion 5.3.2 SAR Image Formation 5.3.3 Coexistence with Point Cloud Pipeline 5.3.4 Elevation Information 5.4 Future Directions 5.4.1 Forward-Facing SAR 5.4.2 SAR for Moving Objects 5.4.3 Gapped SAR 5.5 Conclusion References Chapter 6 Radar Transceiver Technologies 6.1 Background and Introduction to Automotive Radar 6.2 Block Diagram Overview of an FMCW Radar Transceiver 6.3 Challenges with Deeply Scaled CMOS 6.4 Active Devices in CMOS 6.5 Passives in CMOS 6.6 Circuit Architectures Suitable for Advanced CMOS 6.6.1 The Transmit Power Amplifier 6.6.2 The TX Phase Shifter 6.7 The LO/FMCW Chirp Generator 6.8 The Receiver Signal Chain 6.8.1 RX Frontend 6.8.2 Radar RX Baseband 6.9 Summary References Part 2: Challenges and Solutions for the Automotive Environment Chapter 7 Radar Challenges from the Automotive Scene 7.1 Introduction 7.1.1 Range Swath 7.1.2 Imaging Dense Clutter 7.1.3 Simultaneous Transmit and Receive 7.2 Scene Dynamic Range 7.3 Ground Bounce (Unresolved Reflections) 7.4 Multipath (Resolved Reflections) References Chapter 8 Radar Interference 8.1 Introduction 8.2 Motivation and Definitions 8.3 Impacts and Manifestation 8.3.1 LFM/FMCW 8.3.2 PMCW Radar and Mixed Waveforms 8.4 RFI Mitigations 8.4.1 Mitigations Local to the Radar 8.4.2 Global Mitigations: Noncooperative Countermeasures 8.4.3 Global Mitigations: Cooperative Countermeasures 8.4.4 Global Mitigations: Regulations 8.5 Recommendations for the Future 8.5.1 Use Less Energy and Power 8.5.2 Report Confidence 8.5.3 Create a Useful Taxonomy for RFI Mitigation References Chapter 9 The Impacts of Water (Weather) on Automotive Radar 9.1 Introduction 9.2 System Losses 9.2.1 Transmission Loss 9.2.2 Target Loss 9.2.3 Radome Loss 9.3 Array Performance 9.4 Backscattering Phenomenology 9.4.1 Rainfall Backscatter 9.4.2 Road Spray 9.5 Potential Mitigations References Part 3: Integration and System Considerations Chapter 10 Safety Considerations for Radar in Fully Autonomous Vehicles 10.1 Introduction 10.2 What Is Safety? 10.3 Safety Standards 10.3.1 ISO 26262 and ISO 21448 10.3.2 Relationship to Existing Standards and Processes 10.4 Lessons from Industry 10.4.1 Emphasize Understanding over Following Checklists 10.4.2 Embrace Systems Engineering 10.4.3 Address Safety in the Most Appropriate Place 10.4.4 Improve Supplier/Customer Engagement 10.4.5 Recognize the Criticality of a High Quality Safety Manual 10.4.6 Beware the Many Pitfalls of Safety Analysis 10.4.7 Applying Safety to Emerging or Complex Technologies 10.5 Safety Concepts for Level 4 ADS and Implications for Radar 10.5.1 Safety Considerations on Multiple Sensor Modalities 10.5.2 Safety Considerations on Radar Data 10.5.3 Radar FuSa and SOTIF Roots Causes and Mitigations 10.5.4 Safety Considerations Due to Available Radar Technology 10.6 Safety Considerations for Verification and Validation 10.7 Conclusion References Chapter 11 Testing Automotive Radars 11.1 Introduction: Why Is Testing Necessary? 11.1.1 Verification and Validation of System Performance 11.1.2 Conformance to Legal Regulations and Industrial Standards 11.1.3 Safety Performance Assessment 11.2 Measurable Parameters: From Sensor Level to Vehicle Integration 11.2.1 Transmitter Tests 11.2.2 Receiver Test 11.2.3 Antenna and Radome Test 11.2.4 Performance and Functional Tests 11.2.5 Integration Testing 11.3 Test Equipment 11.3.1 General Test Equipment 11.3.2 Radar Echo Generators 11.3.3 Measurement Antennas 11.3.4 Anochic Chambers 11.3.5 Positioners 11.4 Example Test Setups 11.4.1 Transmitter Test Setup 11.4.2 Setup for Sensor Calibration and Performance Tests 11.4.3 Setups for EMC and OOB Testing 11.4.4 Simulating Interference from Other Automotive Radar Transmitters 11.4.5 Exemplary Test Scenario 11.4.6 ADAS Integration Test Bed 11.4.7 ViL Test References List of Acronyms About the Editor About the Authors