1、 Recommendation ITU-R M.2057-1 (01/2018) Systems characteristics of automotive radars operating in the frequency band 76-81 GHz for intelligent transport systems applications M Series Mobile, radiodetermination, amateur and related satellite services ii Rec. ITU-R M.2057-1 Foreword The role of the R
2、adiocommunication Sector is to ensure the rational, equitable, efficient and economical use of the radio-frequency spectrum by all radiocommunication services, including satellite services, and carry out studies without limit of frequency range on the basis of which Recommendations are adopted. The
3、regulatory and policy functions of the Radiocommunication Sector are performed by World and Regional Radiocommunication Conferences and Radiocommunication Assemblies supported by Study Groups. Policy on Intellectual Property Right (IPR) ITU-R policy on IPR is described in the Common Patent Policy fo
4、r ITU-T/ITU-R/ISO/IEC referenced in Annex 1 of Resolution ITU-R 1. Forms to be used for the submission of patent statements and licensing declarations by patent holders are available from http:/www.itu.int/ITU-R/go/patents/en where the Guidelines for Implementation of the Common Patent Policy for IT
5、U-T/ITU-R/ISO/IEC and the ITU-R patent information database can also be found. Series of ITU-R Recommendations (Also available online at http:/www.itu.int/publ/R-REC/en) Series Title BO Satellite delivery BR Recording for production, archival and play-out; film for television BS Broadcasting service
6、 (sound) BT Broadcasting service (television) F Fixed service M Mobile, radiodetermination, amateur and related satellite services P Radiowave propagation RA Radio astronomy RS Remote sensing systems S Fixed-satellite service SA Space applications and meteorology SF Frequency sharing and coordinatio
7、n between fixed-satellite and fixed service systems SM Spectrum management SNG Satellite news gathering TF Time signals and frequency standards emissions V Vocabulary and related subjects Note: This ITU-R Recommendation was approved in English under the procedure detailed in Resolution ITU-R 1. Elec
8、tronic Publication Geneva, 2018 ITU 2018 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R M.2057-1 1 RECOMMENDATION ITU-R M.2057-1 Systems characteristics of automotive radars operating in the frequency band 76
9、-81 GHz for intelligent transport systems applications (2014-2018) Scope This Recommendation specifies the system characteristics of automotive radars operating under the radiolocation service in the frequency band 76-81 GHz. These technical and operational characteristics should be used in compatib
10、ility studies between automotive radars operating in the radiolocation service and systems operating in other services. Keywords Characteristics, protection criteria, automotive radar, intelligent transport systems Abbreviations/Glossary ACC Adaptive cruise control CA Collision avoidance FMCW Freque
11、ncy modulated continuous wave ITS Intelligent transport systems Related ITU Recommendations and Reports Recommendation ITU-R M.1452 Millimetre wave vehicular collision avoidance radars and radiocommunication systems for intelligent transport system applications The ITU Radiocommunication Assembly, c
12、onsidering a) that antenna, signal propagation, target detection, and large bandwidth characteristics for automotive radars are needed to optimally achieve their functions in certain frequency bands; b) that the technical characteristics of radars operating in the radiodetermination service are dete
13、rmined by the needs of the system and may vary widely from band to band; c) that representative technical and operational characteristics of systems operating in frequency bands allocated to the radiodetermination service are necessary to determine the feasibility of introducing new types of systems
14、; d) that procedures and methodologies are needed to analyse compatibility between radars operating in the radiodetermination service and systems operating in other services, recommends that the systems characteristics for automotive radars operating in the frequency band 76-81 GHz for intelligent t
15、ransport systems (ITS) applications as described in Annex 1 should be used for sharing/compatibility studies. 2 Rec. ITU-R M.2057-1 Annex 1 Systems characteristics of automotive radar systems operating in the frequency band 76-81 GHz for intelligent transport system applications 1 Introduction In th
16、e frequency band 76-81 GHz, radar systems in support of enhanced road safety are operated. Evolving demands related to automotive safety applications, including the reduction of traffic fatalities and accidents require a range resolution for automotive radar systems leading to a necessary bandwidth
17、of up to 4 GHz. 2 Technical characteristics of automotive radar systems operating in the frequency band 76-81 GHz Regarding functional and safety requirements, the automotive radar systems operating in the 76-81 GHz range can be separated in two categories: Category 1: adaptive cruise control (ACC)
18、and collision avoidance (CA) radar, for measurement ranges up to 250 metres the typical technical characteristics are listed in Table 1 as Radar A. For these applications, a maximum continuous bandwidth of 1 GHz is required. Such radars are considered to add additional comfort functions for the driv
19、er, giving support for more stress-free driving. Category 2: Sensors for high resolution applications such as blind spot detection, lane-change assist and rear-traffic-crossing-alert, detection of pedestrians and bicycles in close proximity to a vehicle, for measurement ranges up to 100 metres the t
20、ypical technical characteristics are listed in Table 1 as Radar B, Radar C and Radar D. For these high resolution applications, a necessary bandwidth of 4 GHz is required. Such radars directly add to the passive and active safety of a vehicle and are therefore an essential benefit towards improved t
21、raffic safety. The increased requirements for active and passive vehicle safety are already reflected in the requirements for vehicle testing. Radar E operates with a higher field of view to enable high-resolution applications such as pedestrian detection, parking-aid, and emergency braking at low s
22、peed ( 30 km/h). The technical parameters of radiolocation radar systems operating in the frequency bands 76-77 GHz and 77-81 GHz are presented in Table 1. Rec. ITU-R M.2057-1 3 TABLE 1 Automotive radar characteristics in the frequency band 76-81 GHz Parameter Units Radar A(1) Automotive radar For f
23、ront applications for e.g. for ACC Radar B Automotive high-resolution radar For front applications Radar C Automotive high-resolution radar For corner applications Radar D Automotive high-resolution radar Radar E Automotive high-resolution radar Very short range applications (e.g. parking-aid, CA at
24、 very low speed) Sub-band used GHz 76-77 77-81 77-81 77-81 77-81 Typical operating range m Up to 250 Up to 100 Up to 100 Up to 100 Up to 50 Range resolution cm 75 7.5 7.5 7.5 7.5 Typical emission type FMCW, Fast-FMCW FMCW, Fast-FMCW FMCW, Fast-FMCW FMCW FMCW, Fast-FMCW Max necessary bandwidth GHz 1
25、4 4 4 4 Chirp bandwidth GHz 1 2-4 2-4 2-4 2 Typical sweep time s 10 000-40 000 for FMCW 10-40 for fast-FMCW 10 000-40 000 for FMCW 10-40 for fast-FMCW 10 000-40 000 for FMCW 10-40 for fast-FMCW 2 000-20 000 for FMCW 10 000-40 000 for FMCW 10-40 for fast-FMCW Maximum e.i.r.p. dBm 55 33 33 45 33 Maxim
26、um transmit power to antenna dBm 10 10 10 10 10 4 Rec. ITU-R M.2057-1 TABLE 1 (continued) Parameter Units Radar A(1) Automotive radar For front applications for e.g. for ACC Radar B Automotive high-resolution radar For front applications Radar C Automotive high-resolution radar For corner applicatio
27、ns Radar D Automotive high-resolution radar Radar E Automotive high-resolution radar Very short range applications (e.g. parking-aid, CA at very low speed) Max power density of unwanted emissions dBm/MHz 0 (73.5-76 GHz and 77-79.5 GHz) 30 otherwise 30 30 13(2) 30 Receiver IF bandwidth (3 dB) MHz 0.5
28、-1 10 10 10 10 Receiver IF bandwidth (20 dB) MHz 0.5-20 15 15 15 15 Receiver sensitivity(3) dBm 115 120 120 120 120 Receiver noise figure dB 15 12 12 12 12 Equivalent noise bandwidth (kHz) kHz 25 16 16 16 16 Antenna main beam gain dBi Typical 30, Maximum 45 TX: 23 RX: 16 TX: 23 RX: 13 TX: 35 max. RX
29、: 35 max TX: 23 RX: 13 Antenna height m 0.3-1 above road 0.3-1 above road 0.3-1 above road 0.3-1 above road 0.3-1 above road Antenna azimuth 10 dB beamwidth degrees TX/RX: 10 TX: 22.5 RX: 25 TX: 23 RX: 30 TX: 30 RX: 30 TX: 50 RX: 50 Rec. ITU-R M.2057-1 5 TABLE 1 (end) Parameter Units Radar A(1) Auto
30、motive radar For front applications for e.g. for ACC Radar B Automotive high-resolution radar For front applications Radar C Automotive high-resolution radar For corner applications Radar D Automotive high-resolution radar Radar E Automotive high-resolution radar Very short range applications (e.g.
31、parking-aid, CA at very low speed) Antenna azimuth 3 dB beamwidth(4) degrees TX/RX: 5 TX: 12.5 RX: 13.5 TX: 12.5 RX: 16 TX: 16 RX: 16 TX: 27 RX: 27 Antenna elevation -3 dB beamwidth degrees TX/RX: 3 TX/RX: 5.5 TX/RX: 5.5 TX/RX: 5.5 TX/RX: 5.5 (1) Radar type A is related to Recommendation ITU-R M.145
32、2. (2) Maximum power density of unwanted emission is specified at antenna input terminal. (3) The receiver sensitivity is determined using the equivalent noise bandwidth. (4) This parameter is used by the antenna pattern defined in 3 below (3). 6 Rec. ITU-R M.2057-1 3 Antenna pattern The following e
33、quations provide the antenna radiation pattern that could be used in the analysis of interference: (,) = () () = 0 12 for 0 1.152 () = 0 15 15log() for 1.152 with: = arctan (tansin) = 1(cos3 )2+(sin3 )2 = arccos (cos.cos) = where: G(,): gain relative to an isotropic antenna (dBi) G0: Maximum gain in
34、 or near the horizontal plane (dBi) : Absolute value of the elevation angle relative to the angle of maximum gain (degrees) 3: 3 dB beamwidth in the vertical plane (degrees) : Azimuth angle relative to the angle of maximum gain (degrees) 3: 3 dB beamwidth in the azimuth plane (degrees). Antenna patt
35、erns using these formulas for the five radar types defined in Table 1 are presented in Annex 2. 4 Operational characteristics of automotive radar systems operating in the frequency bands 76-77 GHz and 77-81 GHz Automotive radar applications are evolving from providing additional comfort functions, s
36、uch as ACC and CA radar, to functions that significantly add to the passive and active vehicle safety. This requires systems that can detect objects in the close proximity (in the order of 15 metres) of the vehicle, such as pedestrians or bicycles. Such applications require radar sensors that have a
37、 target separation capability of less than 10 centimetres. Radar sensors that provide this resolution require an operating bandwidth of 4 GHz. Radar A type sensors detect the relevant road traffic in order to adapt the speed of the vehicle to that of other vehicles ahead. To satisfy the demands for
38、increased car safety, and depending on the application, one or more radar A type systems may be combined with additional radar B, C, D and E type sensors in one vehicle. Based on the sensor information, the data processing system in the vehicle will trigger the appropriate radar. Rec. ITU-R M.2057-1
39、 7 Radar B, C, D and E type sensors cover the close proximity of a vehicle and will add additional active and passive safety functions, e.g. autonomous emergency braking, active blind spot assistance and lane change assistance. 5 Protection criteria The desensitizing effect on radars operated in thi
40、s frequency band from other services of a continuous wave, frequency modulated continuous wave (FMCW) or noise-like type modulation is predictably related to its intensity. In any azimuth sectors in which such interference arrives, its power spectral density can simply be added to the power spectral
41、 density of the radar receiver thermal noise, to within a reasonable approximation. If the power spectral density of the radar-receiver noise in the absence of interference is denoted by N0 and that of noise-like interference by I0, the resultant effective noise power spectral density becomes simply
42、 I0 + N0. An increase of about 1 dB for the automotive radars would constitute significant degradation. Such an increase corresponds to an (I + N )/N ratio of 1.26, or a protection criterion I/N of about 6 dB. The aggregation factor can be very substantial in the case of certain communication system
43、s, in which a great number of stations can be deployed. The effect of pulsed interference is more difficult to quantify and is strongly dependent on receiver/processor design and mode of operation. In particular, the differential processing gains for valid-target return, which is synchronously pulse
44、d, and interference pulses, which are usually asynchronous, often have important effects on the impact of given levels of pulsed interference. Several different forms of performance degradation can be inflicted by such desensitization. Assessing it will be an objective for analyses of interactions b
45、etween specific radar types. 8 Rec. ITU-R M.2057-1 Annex 2 Antenna pattern examples in transmission for radar types defined in Table 1 M . 2 0 5 7 - 0 1A zi mu t h p at t er n0A n g l e (d eg re es )20 40 60 80 100E l ev at i o n p at t er n10505101520253035A n t en n a p at t er n ra d ar ALevel(dB
46、i)Rec. ITU-R M.2057-1 9 M . 2 0 5 7 - 0 2A zi mu t h p at t er n0A n g l e (d eg re es )20 40 60 80 100E l ev at i o n p at t er n1050510152025A n t en n a p at t er n ra d ar B an d CLevel(dBi)M . 2 0 5 7 - 0 3A zi mu t h p at t er n0A n g l e (d eg re es )20 40 60 80 100E l ev at i o n p at t er n0510152025A n t en n a p at t er n ra d ar DLevel(dBi)30354010 Rec. ITU-R M.2057-1 M . 2 0 5 7 - 0 4A zi mu t h p at t er n0A n g l e (d eg re es )20 40 60 80 100E l ev at i o n p at t er n0510152025A n t en n a p at t er n ra d ar ELevel(dBi)510
