RF-Applications in Vehicles Today and Tomorrow Josef Wenger Environment Recognition DaimlerChrysler AG, Ulm, Germany
Outline Short overview on automotive RF-/microwave applications Automotive radar for driver assistance and safety systems Long Range Radar (LRR) at 77 GHz Short Range Radar (SRR) Regulatory aspects Microwave technologies and components Technologies, devices, circuits / MMICs Modules, assembly and integration Future perspectives of automotive radar Summary and outlook 2
Outline Short overview on automotive RF-/microwave applications Automotive radar for driver assistance and safety systems Long Range Radar (LRR) at 77 GHz Short Range Radar (SRR) Regulatory aspects Microwave technologies and components Technologies, devices, circuits / MMICs Modules, assembly and integration Future perspectives of automotive radar Summary and outlook 3
Automotive Applications of RF- Technology Wireless Airbag Trigger In-Car Communication and Telematic Navigation and Communication Wireless Sensor Data Links (e.g. Engine State) RFID Applications Car-to-Car Communication Radar Sensors (LRR and SRR) Keyless Entry/Go Tire Pressure Monitoring 4
Tire Remote Pressure Entry Monitoring System The driver authorization system assures, that only owners with a valid key are allowed to open the interlock and to start the engine System data (radio link): d= up to 70m f t = 433,92MHz (Europe) 315MHz (USA) Remote control key EIRP = -18dBm L p Sensitivity = -97dBm Modulation = FSK TX P t P r RX Data rate = 1kBit/s L p Pt = P r G t G r 2 Sensitivity 4 π d f t 1 = c G G t r 5
Keyless Entry/Go Active keyless access and driver authorization system By grasping the door handle the key code is interrogated wireless and the vehicle is unlocked The engine can be started by a start/stop button at the gear selector lever Keyless go key approx. 1,5m Higher data rate (10kBit/s) compared to remote control key 6
Navigation with GPS/Galileo 1575.42 MHz (19.05cm) GPS/GSM Antenna 24 Satellites Navigation-Display 7
Tire Pressure Monitoring 0.2 (0.6) bar insufficient pressure reduces tire lifetime by 10% (50%) and increases fuel consumption by 1% (4%) In USA 250000 accidents caused by insufficient tire pressure In USA new cars must be equipped with a tire pressure monitoring system (TPMS) (50% from 1.9.2005 increasing to 100% from 1.9.2007) Courtesy: Atmel Courtesy: Conti-Temic f t =433.92MHz (Europe) / 315MHz (USA) 8
Accidents on the Road (Germany) 400 Fatalities per billion vehicle km 350 300 Total Road Net Urban Roads Rural Roads Motorways 250 200 150 In 2003: 6.605 Fatalities 356.400 Accidents with injuries (Source: ADAC-Motorwelt 1/2004) 100 50 0 1953 1956 1959 1962 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 Year Further reduction of accidents requires new technologies 9
Outline Short overview on automotive RF-/microwave applications Automotive radar for driver assistance and safety systems Long Range Radar (LRR) at 77 GHz Short Range Radar (SRR) Regulatory aspects Microwave technologies and components Technologies, devices, circuits / MMICs Modules, assembly and integration Future perspectives of automotive radar Summary 10
Why Radar? most appropriate technology for automotive applications less unaffected by adverse weather conditions and pollution invisible mounting behind EM-transparent material possible unaffected by external illumination flexible and wide application field possible radar signals have a high information content distance and speed information additional information extraction possible with advanced techniques (object characterization or identification by radar signature) Automotive radar is a key sensor technology for active safety systems 11
Automotive Radar 3. Gen. ACC HRR Accident-Free Driving SRR @ 79 GHz µ-prozessors & µw-hl Distronic (ACC) Distronic Plus, BAS Plus, PAS APG, LCMS, BSD First Experiments Greyhound with AWR 1950 1960 1970 1980 1990 1999 2005 200x 2008 2013 <10 35 24 77 24+77 77 79 Vision GHz 12
First Radar Based ACC (Mercedes-Benz (Distronic)) Key features: Radar principle: Pulse-Doppler Operating frequency: 76.5 GHz Technical data (accuracy): -distance 7-150 m (5 m) - relative velocity -50 - +250 km/h (1 km/h) - FOV (3 db) -4 - +4 (1 ) - beam width (3 beams) 3.4 Update rate: 50 ms Size: diameter 100 mm, depth 50 mm since 1999 A.D.C. Automotive Distance Control Systems 13
Available 77GHz ACC Systems S-Class Mercedes E-Class Mercedes SL, CL, CLK Mercedes DC Actros Audi A8 Lexus RX MAN VOLVO Jaguar XK, XJ BMW 7-, 5-series Cadillac XLR VW Phaeton Honda Inspire 14
77GHz LRR Sensor Suppliers Conti-Temic ADC TRW DENSO Hitachi Mitsubishi Electric Bosch Delphi Fujitsu Ten Introduced in market 15
Specification Next Generation LRR Unit DC-Spec Unit DC-Spec Range m 1 200 Power W < 6 Range Accuracy Velocity Range Velocity Accuracy m km/h km/h ±0,25-100 260 ±0,5 Transmit Power Sensor Size (WxHxD) Sensor Weight Operation Temperature mw mm g C < 10 100*100*50 < 500-40 85 Opening Angle Horizontal deg 20 Storage Temperature C -40 105 Angle Resolution Horizontal deg not def. Mounting Position Offset Horizontal cm ±80 Alignment Offset Horizontal deg ± 3 additiv Mounting Position Offset Vertical cm > 50 Opening Angle Vertical Angle Resolution Vertical Alignment Offset Vertical deg deg deg 4,5 not def. ±2 Misalignment Detection Automatic Adjustment Horizontal Automatic Adjustment Vertical deg - - < 0,1 yes yes Cycle Time ms < 50 Blockage Detection Time sec < 1 Interface - CAN 77 GHz Interference Safety - yes 16
Applications Based on LRR Collision Warning ACC Limited Stop & Go Limited Collision Mitigation Limited Pre-Crash Lexus RX: Pre-Crash Brake Assistant Honda Inspire: Collision Mitigation 17
Applications Based on SRR Precrash Parking aid Blind spot detection Backup parking aid Stop & Go for ACC Rear crash collison warning Collision warning Collision mitigation Blind spot detection Lane change assistent Complete surround sensing up to 30 m with 8 sensors Multiple applications with one kind of sensor possible 18
Requirements for Different SRR Applications Frequency band Bandwidth Resolution R 24,000-24,250 GHz 250 MHz 0,6 m 21-26GHz 5 GHz 0,03 m 76-77 GHz 1 GHz 0,15 m 77-81 GHz 4 GHz 0,0375 m 19
24 GHz UWB SRR Robust technology: Widely independent of weather, daylight conditions or soiling of sensors or object High local resolution: Allows object separation and object tracking Economic, efficient technology: 24 GHz Components widely used = off - the - shelf technology Today s 76 GHz ACC technology for SRR applications not applicable (Substantial development still needed) 24 GHz UWB SRR can contribute to the enhancement of road safety now (!) 20
24 / 77 GHz SRR Developments Tyco / M/A-Com TDK s.m.s. GmbH Siemens-VDO InnoSent / Hella Valeo MTS GmbH 24 (±2.5) GHz Hitachi 76-77 GHz 21
Regulatory Situation The US-Frequency Administration Authority (Federal Communications Commission) allocated the frequency for SRR in summer 2002 without time limitation and without restriction of the car fleet penetration. European 2-Phase Plan 24/79 GHz 2005 2009 2013 Report Sunset date Production + Use Use 24 GHz Development Production + Use 79 GHz Regulation 24 GHz: Time and quantity restrictions of the car park penetration of cars with 24GHz Short Range Radar. Regulation 79 GHz: Frequency is allocated, no restrictions, but technically not yet available. 22
Radar Based Functions in the New Mercedes Benz S-Class Combination of one 76.5 GHz Long Range Radar (DISTRONIC) six 24 GHz Ultra-Wide-Band (UWB) Short Range Radar 23
DISTRONIC Plus in the New Mercedes Benz S-Class Combination of 76.5 GHz Long Range Radar (DISTRONIC) 6 x 24 GHz Ultra-Wide-Band (UWB) Short Range Radar 24
Radar System in the New Mercedes Benz S-Class Specification: Speed range 0-200 km/h Distance range 0.2-150 m Applications: Brake Assist PLUS PRE-SAFE Stop (and Go) Parking Assist 25
PRE-SAFE Bremse 26
Outline Short overview on automotive RF-/microwave applications Automotive radar for driver assistance and safety systems Long Range Radar (LRR) at 77 GHz Short Range Radar (SRR) Regulatory aspects Microwave technologies and components Technologies, devices, circuits / MMICs Modules, assembly and integration Future perspectives of automotive radar Summary 27
Challenges for Automotive Radar Components Low-cost, high-volume production (high level of integration, high yield) High efficiency, low noise High reliability Wide operation temperature range (-40 C to >85 C) Packaging Prepared for automated assembly and testing routines 28
Technologies for Automotive Radar Systems GaAs MMICs (available up to 77GHz) MESFET (< 40GHz) HBT (< 40GHz) P-HEMT (> 40GHz) Si/SiGe (emerging, 24GHz circuits) HBT (< 25GHz) SIMMWIC (> 60GHz) MEMS (emerging, first devices) SiGe??? => Research Project KOKON 29
MMICs for Automotive Radar Front- Ends 19.125 GHz MOD 38.25 GHz x2 x2 OSC40 MFC 38/76 DMIX 77 IF2 IF1 OUT 76.5 GHz RF1 RF2 19.125 GHz MOD ums OUT ums IF1 ums IF2 RF1 RF2 Block-diagram and MMIC chip set for a 77GHz automotive radar Block diagram of the 77GHz fully MMIC module for a two-frequency-cw monopulse radar 30
ACC Radar Front-End MS-to-WG transition A.D.C. ARS200 ACC sensor: MMIC chip VCO (UMS) with an external resonator on alumina subsequent multiplication and amplification (UMS), pin-diode based chip for the switching of the three antenna beams (M/A-Com) hybrid mixer soft-board MMICs alumina 31
BMBF-Funded Project KOKON Project leader Sensor specification and requirements Chip-Supplier System-Supplier Vehicle packaging and design issues Sensor performance and application Sensor test and evaluation 32
Outline Short overview on automotive RF-/microwave applications Automotive radar for driver assistance and safety systems Long Range Radar (LRR) at 77 GHz Short Range Radar (SRR) Regulatory aspects Microwave technologies and components Technologies, devices, circuits / MMICs Modules, assembly and integration Future perspectives of automotive radar Summary 33
HRR Imaging Performance 120 m 8 m 34
Design Parameters System parameters for a radar transceiver with sensitivity -20 dbsm @ 150m (straight forward pulse-doppler approach): assumed antenna gain 35dBi 1 lateral resolution frequency 76,5 GHz transmitter power 20 mw pulse length 6,7 nsec ZF-bandwidth = sampling rate 150 MHz receiver noise 7 db pulse repetition frequency (PRF) 71 khz number of Doppler bins 512 1m range resolution 1km/h speed resolution 35
Summary Automotive radar is a key technology for driver assistance and safety features Using LRR and SRR different novel safety systems are feasible For the next decade, new cost-effective technologies are required for wide market penetration and for the introduction of SRR especially at frequencies around 79 GHz 36