ISO/DIS 13228:2026(en)

ISO/TC 22/SC 32

Secretariat: JISC

Date: 2026-01-12

Road vehicles — Test method for automotive lidar

© ISO 2026

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Contents

Foreword 5

Introduction 6

1 Scope 7

2 Normative references 7

3 Terms and definitions 7

4 Test method for lidar performance 13

4.1 Performance specifications 13

4.1.1 Range capability 13

4.1.2 Range precision 15

4.1.3 Range trueness 16

4.1.4 Angular resolution 17

4.1.5 Angular precision 21

4.1.6 Angular trueness 24

4.1.7 Field of view range – FOV 25

4.1.8 Frame frequency 27

4.1.9 Scan point frequency 27

4.1.10 Point cloud density 28

4.1.11 Radial velocity 30

4.1.12 Radial separability 31

4.1.13 Angular separability 33

4.2 Performance characteristics 34

4.2.1 Anti-interference 34

4.2.2 Interstitial points 38

4.2.3 Ghost points 40

4.2.4 Blooming 44

Annex A (informative) Examples of lidar applicable scenarios 46

A.1 Applicable scenarios 46

A.2 Non-applicable scenario 46

Annex B (informative) Description of applicability of test items 47

Annex C (informative) Test apparatus 48

C.1 Low reflectivity test chamber 48

C.1.1 Size 48

C.1.2 Covering Materials 48

C.2 Target 48

C.2.1 Surface Characteristics of Diffuse Reflectance Targets 48

C.2.2 Reflectance Requirements 49

C.2.3 Calibration of Reflectance 49

C.2.4 Calibration Validity Period 49

C.2.5 Recommended targets List 49

Annex D (informative) Point estimation and interval estimation 50

D.1 Point estimation 50

D.2 Interval estimation 50

Annex E (informative) Highly reflective target 52

Bibliography 53

Foreword

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This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 32, Electrical and electronic components and general system aspects.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Introduction

Automotive lidar systems are critical in modern road vehicles, contributing to advanced driver assistance systems and autonomous driving technologies. These systems use lidars to generate accurate three-dimensional representations of the surrounding environment, enabling safer and more reliable vehicle operation in various driving conditions.

The performance of automotive lidar systems is essential for their effective integration into vehicle safety systems. Given the importance of accuracy, reliability, and environmental adaptability, standardized testing methods are needed to ensure lidar systems meet the necessary performance requirements.

This document provides a comprehensive methodology for testing the performance of automotive lidar systems. This document outlines procedures for evaluating key performance parameters, such as range trueness, resolution, object detection capabilities, and robustness under specific environmental conditions. By establishing uniform testing protocols, this document aims to support developing and deploying of high-quality lidar systems that can reliably enhance vehicle safety and automation.

Road vehicles — Test method for automotive lidar

This standard applies to lidars installed on road vehicles to measure or detect the surroundings of the vehicle.

This standard applies to lidars used on all types of road vehicles regardless of vehicle classifications, including passenger cars, buses, commercial vehicles, trailers, etc.

NOTE The definition of “Road Vehicles” includes M1-M3, N1-N3, and L6-L7 according to Consolidated Resolution on the Construction of Vehicles (R.E.3).

This document specifies a series of test methods to assist in evaluating the performance of lidars, the tests should cover the following:

1. The common performance specifications (e.g., Range capability, Range precision)

2. The common performance characteristics (e.g., Anti-interference, Ghost points)

3. Possible alteration of performance test caused by environmental conditions

4. Lidar performance for the union of both ADAS or AD application scenarios

This document does not specify test methods for reliability, functional safety, and cybersecurity.

This document defines terms in the context of test methods for automotive lidar.

This document provides an overview of applicable scenarios of automotive lidar (see Annex A).

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

There are no normative references in this document.

For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp

— IEC Electropedia: available at https://www.electropedia.org/

3.1

lidar

light detection and ranging

system consisting of 1) a photon source (frequently, but not necessarily, a laser), 2) a photon detection system, 3) a timing circuit, and 4) optics for both the source and the receiver that uses emitted laser light to measure ranges to or properties of solid objects in the atmosphere

Note 1 to entry: See Figure 1.

Figure 1— Illustration of lidar system

[SOURCE: ISO/TS 19130-2:2014, 4.40]

3.2

point cloud

collection of data points in 3D space

Note 1 to entry: The distance between points is generally non-uniform and hence all three coordinates (Cartesian or spherical) for each point must be specifically encoded.

Note 2 to entry: See Figure 2.

Figure 2— Point cloud illustration of pedestrian

[SOURCE: ISO/TS 19130-2:2014, 4.51]

3.3

valid point

data point (in a point cloud) to which real-world object(s) corresponds

3.4

DUT

product being tested using the methods described in this document

3.5

true positive

TP

correct measured value in positive results, that is, the case where both the measured and the correct results are positive

Note 1 to entry: TP refers to the valid points in a frame of point cloud that meet the trueness and precision requirements.

[SOURCE: ISO/TR 27877:2021, 3.1.4]

3.6

false positive

FP

incorrect measured value in positive results, that is, the case where the measured value is positive but the correct one is negative

Note 1 to entry: FP refers to the invalid points in a frame of point cloud that do not meet the trueness and precision requirements.

[SOURCE: ISO/TR 27877:2021, 3.1.6]

3.7

probability of detection

PoD

true positive rate

probability rate of valid points (3.3) in a single measurement and/or accumulation of measurements of a single target

PoD (d=…m)

where

Note 1 to entry: The probability of detection is calculated as the ratio of the number of valid points to the number of theoretical points.

Note 2 to entry: Dependencies exist with background noise, reflectance of the target, acceptance margin of range and other properties.

3.8

measurement precision

distribution of measurements obtained by repeated measurements on the same objects under specified conditions

Note 1 to entry: The precision is expected to be given in sample standard deviations. (See Figure 3)

Figure 3— Illustration of measurement trueness and precision

Note 2 to entry: Mathematical descriptions for sample standard deviation (s):

where

is the number of points

is a specific physical quantity

is the arithmetic mean of the measured value

3.9

measurement trueness

the difference between the measured average value and its true value

Note 1 to entry: The trueness is expected to be given in Figure 3.

Note 2 to entry: Mathematical descriptions for trueness ():

where

3.10

range capability

the minimum and maximum distance at which the lidar (3.1) can detect the object with the specified reflectivity and environmental conditions.

Note 1 to entry: These conditions include light intensity, POD (3.7), noise rate and object orientation.

3.11

range precision

measurement precision (3.8) of the range result

3.12

range trueness

measurement trueness (3.9) of the range result

3.13

angular resolution

angle formed by the connection between two adjacent detection points and the origin of the three-dimensional coordinates in the azimuth or elevation directions

Note 1 to entry: The angular resolution of lidar can be categorized into azimuth angular resolution and elevation angular resolution.

3.14

angular precision

measurement precision (3.8) of the angular temporal position

3.15

angular trueness

measurement trueness (3.9) of the angular temporal position

3.16

field of view range

FOV

angle between the two outermost valid edge points

Note 1 to entry: The FOV contains both the horizontal FOV and the vertical FOV.

3.17

frame

capturing of the entire FOV (3.16) (horizontal and vertical)

3.18

frame frequency

the frequency at which the lidar (3.1) detects a frame

3.19

scan point frequency

the number of theoretical scan points output by the lidar (3.1) per unit time

3.20

point cloud density

number of detectable points per solid angle

3.21

radial velocity

radial component of the relative velocity between the target and the lidar using the Doppler shift

3.22

radial velocity precision

measurement precision (3.8) of the radial velocity result

3.23

radial velocity trueness

measurement trueness (3.9) of the radial velocity result

3.24

radial velocity capability

the minimum/maximum radial velocity (3.21) at which the lidar (3.1) can detect the relative-radial velocity with the specified reflectivity and environmental conditions

3.25

radial separability

minimum deviation in radial distance at which two targets can be separated

3.26

angular separability

minimum deviation in azimuth or elevation angle at which two targets can be separated

3.27

anti-interference

property of a lidar that reduces the interference on the reception of useful laser pulse signal

Note 1 to entry: The source of interference in the test includes lidar and environmental light.

Note 2 to entry: Interference can generate false positives (3.6) in the point cloud (3.2).

3.28

interstitial point

false positive (3.6) that occur between two surfaces (one front and one rear) when a laser beam hits both the surfaces simultaneously

Note 1 to entry: See Figure 4.

Figure 4— Illustration of interstitial points

3.29

ghost points

temporally stable reported false positive (3.6) detection in the point cloud (3.2), originating from internal effects or external multi path propagation

3.30

blooming

presence of false positive (3.6) outside the edge of the target in the point cloud (3.2) when the lidar (3.1) scans a highly reflective target

Note 1 to entry: See Figure 5.

Figure 5— Illustration of blooming

The lidar test items of different technical route lidars will be different. Please refer to Annex B for the test items.

Purpose

This test is intended to measure the minimum and maximum distance at which the lidar can detect the object with the specified reflectivity and environmental conditions.

Test condition

The following test conditions shall apply, if there is no number given in the specification, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: Ambient light measurement is made by placing the sensing direction of the light sensor(s) in the same direction as the direction that the lidar is aiming. Measurement can be performed by placing one or more light sensors. For testing in outdoor environments, such as test tracks, a luxmeter shall be used to measure ambient light levels in lux. For light sources operating within the same spectrum as the DUT, such as the infrared spectrum, a photodiode detector shall be used to measure ambient light irradiance in W/m². The wavelength interval and range of the light source shall also be stated. (the vertical component to the target surface is recommended 75 k lux to 100 k lux for this test, actual measured value shall be recorded)

— Target reflectivity: 10 %

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Outside temperature: -40 °C ~ 85 °C

— Visibility: >20 km

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

a) Target with 10 % reflectivity and a size larger than that of a single light spot of the DUT;

NOTE For a DUT where a single light spot does not span multiple resolution, the minimum target size calculation refers to formula (1), which ensures that there are at least four complete light spots on the target.

(1)

where

is width of target

is the test distance

is the specification of DUT’s azimuth angular resolution

is the specification of DUT’s elevation angular resolution

is a small quantity not greater than

is a small quantity not greater than

Figure 6 — Illustration of Formula (1)

b) DUT (Can be rotated to access different area of the FOV);

c) Possibility to change the distance between target and DUT.

Test procedure

a) Place the DUT or target within the max. and min. distance in …m steps to target or DUT and record at least n seconds at each distance;

b) Calculate the total number of theoretical points on the target at each distance, and count the points that meet the trueness and precision requirements as the number of valid points;

c) Evaluate the PoD or true positive rate at each distance;

d) Determine the range at a PoD of … %;

e) Rotate the lidar horizontal angle or pitch angle, repeat steps a) to d), and measure the range capability of multiple positions within the FOV.

NOTE The distance measurement value of a point on the target is distance converted into the horizontal distance from the lidar ranging center to the target.

Data processing

PoD or True positive rate.

Purpose

This test is intended to determine the measurement precision of the range result.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2 (recommended 75 klux to 100 klux for this test; actual measured value shall be recorded)

— Target reflectivity: 10 %

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Outside temperature: -40 °C ~ 85 °C

— Visibility: >20 km

— Defined distance: d (It is recommended to select multiple distance values, including a maximum distance and a minimum distance)

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

a) Target with 10 % reflectivity and a size larger than that of four complete light spots of the DUT (see 4.1.1.3);

b) DUT (Can be rotated to access different area of the FOV).

Test procedure

a) Place the target in the defined distance d to the DUT and record at least m seconds;

b) Evaluate the measurement precision of the n frames in terms of sample standard deviation;

c) Rotate the DUT and repeat steps a) and b) to measure the range precision of other positions within the FOV.

Data processing

Calculating sample standard deviation, using Formula (2).

(2)

where

are distance results of frame i

is mean distance result

is the number of frames

NOTE Methods for characterizing test results refer to Annex D.

Purpose

This test is intended to determine the measurement trueness of the range result.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2 (recommended 75 klux to 100 klux for this test; actual measured value shall be recorded)

— Target reflectivity: 10 %

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Outside temperature: -40 °C ~ 85 °C

— Visibility: >20 km

— Defined distance d

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

a) Target with 10 % reflectivity and a size larger than that of four complete light spots of the DUT (see 4.1.1.3);

b) DUT (Can be rotated to access different area of the FOV);

c) Possibility to change the distance between target and DUT.

Test procedure

a) Place the target in the defined distance d to the DUT and record at least for n seconds;

b) Evaluate the measurement trueness of the n seconds;

c) Rotate the DUT and repeat steps a) and b) to measure the range trueness of other positions within the FOV.

Data processing

Calculating trueness, using Formula (3).

(3)

where

is defined distance

is mean distance

NOTE Methods for characterizing test results refer to Annex D.

Purpose

This test is intended to determine the resolution of the specified angle range.

The test method used in this test item is not suitable for random scanning pattern lidar.

Test condition

The test shall be conducted under the following conditions. If no specific values are provided in the specification, the values can be independently selected. The selected values shall be documented alongside the test results.

— Target reflectivity: … % (recommended 3 %~ 95 %)

— Target dimensions: … x … m (e.g.,1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23  5 °C)

NOTE See Annex C for more information.

Test setup

a) A target with different reflectivity regions forming boundaries with each other (e.g., the reflectivity of the left half is 3 %, and the reflectivity of the right half is 95 %);

b) Point cloud visualization system;

c) DUT (Can be rotated to access different area of the FOV. The parameters of turntable to be used in the test shall be documented together with the test results).

Test procedure

a) Place the target in …m (e.g., d_min + 10 m) distance to the DUT;

b) Measure and record the angle of DUT, and record the original point cloud of the current angle for a period of time or multiple frames;

c) Choose the point near the middle of one region as the first point. Rotate or tilt the DUT so that the points on the target to be shifted (It is recommended that the rotation or tilt angle does not exceed one tenth of the declared angular resolution);

d) Repeat steps c) and d) until the first point enters the middle of another region, The rotation process diagram is as follows;

Figure 7 — Illustration for angular resolution scanning approach

e) Perform steps c) through e) for the second point (Recommended to choose the point nearby the first point as the second point.

NOTE d_min is claimed in user manual of DUT.

Data processing

The angular resolution can be obtained by calculating the intensity curve of the selected points or the PoD curve of the points near the edge of the target.

Detailed calculation for angular resolution by intensity curve is as follows.

a) Deriving I_max (maximum value of intensity) and I_min (minimum value of intensity) of first points and second points (Derive I_max and I_min by average of multi points(or frames) on high and low reflectivity region);

b) Deriving I_mid (middle value of intensity) by Formula (4);

(4)

c) Deriving angle of first point at I_mid(θ_{first_mid}) and angle of second point at I_mid(θ_{second_mid}) by linear interpolation (Formula (5)) (Perform linear interpolation (Formula (5)) using the closest points on either side of the middle intensity value (I_mid) and find at each trace of first points and second points);

Key

1 target

Figure 8 — Illustration for linear interpolation

(5)

d) Find angular resolution() by Formula (6);

(6)

Figure 9 — Illustration for angular resolution calculation by intensity

Detailed calculation for angular resolution by PoD curve is as follows.

a) In the original point cloud, select adjacent points near the edge of the target and calculate the curve of their PoD changing with angles;

Figure 10 — Illustration for angular resolution calculation by PoD

b) Deriving fitting Points corresponding to PoD equals 50 % of curve K, M, N by linear interpolation (Formula (5)) (Perform linear interpolation (Formula (5)) using the closest points on either side of the PoD equals 50 %;

c) Find the angle θ_K corresponding to PoD equals 50 % in curve K, angle θ_M corresponding to PoD equals 50 % in curve M, angle θ_N corresponding to PoD equals 50 % in curve N;

d) Find the angle θ_K corresponding to PoD equals 50 % in curve K, angle θ_M corresponding to PoD equals 50 % in curve M, angle θ_N corresponding to PoD equals 50 % in curve N. Calculate angular resolution θ_resolution by Formula (7), (8) or (9).

(7)

(8)

(9)

NOTE Choose Formula (7) means using the average angular resolution between three adjacent points as the angular resolution. Choose Formula (8) or (9) means using the angular resolution between two selected adjacent points as the angular resolution.

Purpose

This test is intended to determine the precision of the specified angle range.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2

— Target reflectivity: … % (recommended 10 %~ 90 %)

— Target: round target (size approximately 20 pixels), corner reflector (smaller than beam size), diffuse sphere target (larger than beam size), or flat target (e.g., 2 m x 2 m)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Outside temperature: -40 °C ~ 85 °C

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

a) Round target (size ~20 pixels), corner reflector (smaller than beam size), diffuse sphere target (larger than beam size), or tilted flat target (e.g., 2 m x 2 m);

b) DUT (Can be rotated to access different area of the FOV).

Test procedure

a) Place the DUT in …m distance to the target;

b) Rotate the DUT/move the target (e.g., in 10°steps) in order to cover the defined FOV and record n frames for each rotation;

c) Evaluate and calculate:

— When using round target, corner reflector or diffuse sphere target, evaluate the center angle for each frame respectively and calculate the measurement precision using all center angles for each rotation stage position respectively.

— Or when using tilted flat target, select the point nearby target center for each frame respectively and calculate the measurement precision for each rotation stage position respectively.

Data processing

The data processing for angular precision varies depending on the type of target selected.

For round target, corner reflector or diffuse sphere target:

Record n frames in each rotation stage position. Evaluate the center angle of the target for each rotation stage position (α₁, α₂, ..., α_j, …) and each frame i using center of mass or minimum bounding circle. Calculate the standard deviation of the center angles of the n frames (for each rotation stage position respectively).

Figure 11 — Illustration for center angle calculation for each rotation stage position

The formula of detected center angle of the target for rotation stage position α_j:

(10)

where

is center angle for frame i at rotation stage position α_j

is the frame number at rotation stage position α_j

n is number of frames captured at rotation stage position α_j

NOTE1 When using a corner reflector (which must be smaller than the beam size), it functions as an ideal ‘point source’. Therefore, the center angle () should be taken as the direct angular position of peak-intensity point during a rotation. The angular step size during rotation should be smaller than both the lidar’s angular resolution and beam width to accurately capture the peak intensity.

NOTE2 When using a diffuse sphere (which is larger than the beam size), the sensor records a point cloud arc from the sphere’s surface. Therefore, the center angle () should be calculated by applying a geometric ‘Sphere Fitting’ algorithm to the point cloud in order to determine the sphere’s virtual center.

The formula of angular trueness for rotation stage position α_j:

(11)

where is expected center angle for rotation stage position α_j

The formula of angular precision for rotation stage position α_j:

(12)

NOTE Methods for characterizing test results refer to Annex D.

For tilted flat target:

For each rotation stage position, select the DUT reported points nearby the center of the target and calculate the angular precision as follows.

a) Calculate the ‘actual’ angle of each point, using Formula (13)

(13)

where:

calculated ‘actual’ angle of the i-th point

reported range of the i-th point output by the DUT

distance between the center of the DUT and the center of the target

angle between the target plane and the DUT normal at turntable's zero rotation angle.

Figure 12 — Illustration for angular precision test method

NOTE The recommended test distance is 30 m~50 m and tilted angle 10 degrees. The test distance and tilted angle can be selected based on the range precision and the angular precision of the DUT.

b) Calculate the angle deviation between the reported angle and the ‘actual’ angle of the points, using Formula (14)

(14)

where:

angle deviation of the i-th point

reported angle of the i-th point output by the DUT

c) Calculate the standard deviation of the angle deviation as the angular precision.

NOTE 1 The angular estimation error will arise due to the ‘mixing’ of range precision and angular precision as a function of the expected range precision of the DUT, distance of the target and tilting of the target.

NOTE 2 The range precision of the DUT (usually measured on a perpendicular target) might be affected by the tilting of the target.

NOTE 3 Methods for characterizing test results refer to Annex D.

Purpose

This test is intended to determine the trueness of the specified angle range.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2

— Target reflectivity: … % (recommended 10 %~ 90 %)

— Target: round target (size ~20 pixels), corner reflector (smaller than beam size) or diffuse sphere target (larger than beam size)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Outside temperature: -40 °C ~ 85 °C

NOTE See Annex C for more information.

Test setup

Refer to Clause 4.1.5.3 for test setup.

Test procedure

d) Place the DUT in …m distance to the target;

e) Rotate the DUT/move the target (e.g., in 10°steps) in order to cover the defined FOV and record n frames for each rotation;

f) Evaluate the center angle (azimuth and elevation) of the target for each frame respectively;

g) Calculate the measurement trueness using all center angles for each rotation stage position respectively.

Data processing

Refer to Formula (11) for angular trueness calculation.

Purpose

This test is intended to determine the Field of view range – FOV.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2

— Target reflectivity: … % (recommended 10 %~ 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23  5 °C)

NOTE See Annex C for more information.

Test setup

The following indication of the test setup to be used.

Figure 13 — Illustration for Field of view range – FOV

Test procedure

a) Place the target in a distance of …m away from DUT where the POD > 95 % (target with Lambertian reflectivity, no retroreflective target);

b) Place the DUT on a rotation stage with sufficient dynamic range to cover the entire FOV of the sensor;

NOTE Recommend to use a target which covers in horizontal or vertical direction at least an angle interval, which corresponds to the resolution in horizontal or vertical direction.

c) Rotate the sensor in the mathematically negative angular direction until the POD of the outermost scan points of the DUT (max. pos. angle of DUT) on the target drops below 20 %;

d) Rotate the sensor in the mathematically positive angular direction until the POD of the outermost scan points of the DUT (max. neg. angle of DUT) on the target drops below 20 %.

NOTE The target distance is recommended to select a distance where the lidar does not reduce the angular resolution.

Data processing

a) Evaluate the outermost two angles of the rotation stage, where the POD dropped below 20 %

b) Calculate the difference between the two angles, which is the resulting FOV

Purpose

This test is intended to determine the frequency at which the lidar detects a frame.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2

— Target reflectivity: … % (recommended 10 %~ 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23  5 °C)

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test has to be documented together with the test results.

Test procedure

a) Start the DUT and record at least n seconds;

b) Capture the data alongside with the timestamp from an external clock with high precision.

Data processing

Evaluate the minimum, maximum and average time interval between the receiving of two consecutive full frames using the timestamps of the external clock.

Purpose

This test is intended to determine the number of theoretical scan points output by the lidar per unit time.

This method is not suitable for lidars with uneven angular resolution

Test condition

As it is a theoretical computation, this chapter is not applicable.

Test setup

As it is a theoretical computation, this chapter is not applicable.

Test procedure

As it is a theoretical computation, this chapter is not applicable.

Data processing

Scan point Frequency = Horizontal FOV/Horizontal Resolution * Vertical FOV/Vertical Resolution * Frame Frequency* Number of Echoes

NOTE Frame frequency (min, max, average) to be considered to be applicable for all types of lidar.

Theoretical Example:

— Horizontal FOV -> 120°

— Horizontal Resolution -> 0,1°

— Vertical FOV -> 20°

— Vertical Resolution -> 0,2°

— Frame Frequency -> 100 ms = 10 Hz

— Number of Echoes -> 3

Scan point Frequency = (120/0,1+1) * (20/0,2+1) * 10 * 3 =3 639 030 scan points/sec

Purpose

This test is intended to determine the maximum number of detection points per solid angle by the lidar.

NOTE The test method used in this test item is not suitable for random scanning pattern lidar.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2

— Target reflectivity: … % (recommended 10 % ~ 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23  5 °C)

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

a) Target min 1°x1°;

b) DUT (Can be rotated to access different area of the FOV);

c) Possibility to change the distance between target and DUT.

Test procedure

a) Place a target in a distance where it covers at least 1° azimuth x 1° elevation;

b) Make sure the target is seen with a probability of detection POD ≥ 90 % (e.g., use 90 % reflective target or retro reflective target);

c) Record for n seconds;

d) If the sensor under test has a different angular resolution in certain angle intervals, repeat the test for each of these intervals;

e) In case the sensor under test varies the shooting pattern (e.g., based on the detection of targets in the regions of interest). The measurement shall take place including the first scan, where the sensor has no information where the target is located.

Data processing

a) Evaluate the maximum number of scan points detected in an angle interval of azimuth φ = elevation θ (quadratic >1 deg²) within the true positive scan points from the target for each frame

b) Double returns or echoes at the same angle count as one scan point

c) Calculate the average, maximum and minimum point cloud density of the individual measurements as follows: Point cloud density = # Scan points/solid angle (solid angle = φ * θ)

d) The final result is given in the unit “Scan points/deg²” at a certain frequency that shall be stated

e) In case the sensor under test has a random or varying shooting pattern more scans can be averaged and the updated frequency shall be stated (e.g., 30 Scan points/deg² at 10 Hz, 60 Scan points/deg² at 5 Hz)

Purpose

This test is intended to determine the radial velocity precision, trueness and capability.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2

— Target reflectivity: … % (recommended 10 %~ 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Outside temperature: -40 °C ~ 85 °C

NOTE See Annex C for more information.

Test setup

The radial velocity output by the DUT shall be compared against the true relative velocity between the DUT and the target, as obtained from the reference system.

Equipment or software to be used in the test is shown as below.

a) DUT (Can be rotated to access different area of the FOV) ;

b) Possibility to change the distance between target and DUT .

Alternatively, this test may be conducted by fixing the target and moving the DUT.

NOTE 1 See Annex C for more information.

NOTE 2 The recommended velocity trueness for the target is <0,5 kph, and this value should be recorded during the test.

Figure 14 — Illustration for radial velocity test method

Test procedure

a) Place the DUT and target as in Figure 14;

b) Move either or both the DUT and the target with an increasing relative velocity;

c) The velocity should start at 0 m/s and be increased gradually during the measurement.

Data processing

a) The values for radial velocity precision and trueness shall be calculated using definitions of 3.8 and 3.9 respectively;

b) In this context, the radial velocity output by the DUT shall be used as the statistical sample, but only those data points that clearly correspond to the target shall be included.

c) The reference value shall be the relative velocity between the DUT and the target as measured by the reference system.

d) Radial velocity capability shall be recorded.

Purpose

This test is intended to determine minimum radial distance at which two targets can be separated.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2

— Target reflectivity: … % (recommended 10 %~ 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23  5 °C)

— Defined distance: d

NOTE See Annex C for more information.

Test setup

The following indication of the test setup to be used.

Figure 15 — Illustration for radial separability

Test procedure

a) Place and align the target in the defined distance d to the DUT and record at least n seconds;

b) Evaluate the distance measurement distribution and calculate the standard deviation;

c) Change the radial position of the sensor by [resolution / j] meter and repeat step 2 and 3 j times;

d) Calculate the minimum, maximum and standard deviation;

e) Multiply with 4 to get the min, max and average separability.

Data processing

Standard deviation is given in Formula (15).

(15)

where

n is number of frames

j is the number of measurements (e.g., 30)

dist is the distance measurement

with Minimum, Maximum and Average Separability given in Formula (16).

(16)

Purpose

This test is intended to determine the minimum deviation in azimuth or elevation angle at which two targets can be separated.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2

— Target reflectivity: … % (recommended 10 %~ 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23  5 °C)

— Defined distance: d

NOTE See Annex C for more information.

Test setup

The following indication of the test setup to be used.

Figure 16 — Illustration for angular separability

Test procedure

a) Place and align the adjustable targets at defined distance d to the DUT with angular separation at minimum;

b) Extend the angular separation of the targets until a first non-continuous point cloud pattern is generated (POD in gap < 20 %) and record for at least n seconds;

c) Change the angular position of the sensor by [resolution / j] degree in the direction of interest (azimuth or elevation) and repeat step b) and c) j times;

d) Calculate the minimum, maximum, and standard deviation of measured angular separation.

Data processing

Standard deviation is given in Formula (17).

(17)

where

g is the real target gap

j is the number of measurements (e.g., 30)

Lidar interfering

Purpose

This test is intended to validate a lidar’s capability of resisting external interference from another lidar.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: recommended ≤100 lux (An irradiance measurement over the wavelength interval of operation for the lidar would provide a useful indication of potential background light and actual measured value shall be recorded)

— Temperature: room temperature (e.g., 23  5 °C)

— Environment conditions: relative humidity 25 %~75 %

— Test location: Laboratory with low reflectivity walls (≤10 %)

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

— Mounting apparatus (any construction where the sensors are mounted stably)

— Point cloud visualization system

— Target reflectivity: … % (recommended 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, additional target can be used and shall be documented)

— Low reflectivity test chamber (specifications refer to Annex C.1)

— Two lidars of the same model (one as the DUT and the other as interfering source)

NOTE Other lidars can also be used as interference sources to perform additional testing.

Test procedure

a) Mount the DUT (the height is recommended to be 1 m);

b) Mount the interfering lidar at the same height as the DUT, with the center of FOV aligned relative to each other. The distance from the interference source to the DUT's measurement origin, denoted as d, shall be 0,5 m. For detailed test scenario, please refer to Figure 17;

c) Record more than 100 frames of point cloud without activation of interference source. Count the total number of scan points, denoted as N;

d) Record more than 100 frames of point cloud with activated of interference source;

e) Compare the difference in point cloud between step c) and d). Count the total number of all points that are d_n m away from the original point cloud, denoted as N_FP;

f) Vary the distance between the interference sources, and repeat step c) to e);

g) Mount the interfering lidar at the same height as the DUT, with the center of FOV facing same target. The distance from the interference source to the DUT's measurement origin, denoted as d, shall be 0,5 m. For detailed test scenario, please refer to Figure 18;

h) Record more than 100 frames of point cloud without activation of interference source. Count the total number of scan points, denoted as N;

i) Record more than 100 frames of point cloud with activated of interference source;

j) Compare the difference in point cloud between step h) and i). Count the total number of all points that are d_n m away from the original point cloud, denoted as N_FP;

k) Vary the distance between the interference sources, and repeat step h) to j).

NOTE 1 Make sure there is a beam-facing area in each scanning cycle in step b).

NOTE 2 d_n should be documented in report,and d_n is recommended 0,6 m.

Figure 17 — Illustration of a setup for evaluating lidar with interference from another lidar

Figure 18 — Illustration of lidar co-directional interference

Data processing

Calculate the stability of the point cloud, expressed as a percentage, using Formula (18).

(18)

where

is the theoretical number of valid points within a fixed time period

is the number of false positives within a fixed time period

S is the stability of point cloud

In addition, calculate the maximum stability (Defined as S_max) of per unit angle point clouds in FOV. A higher value of S corresponds to a better capability of resisting external interference from another lidar.

Light interfering

Purpose

This test is intended to validate a lidar’s capability of withstanding external interference from a light source.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: recommended ≤100 lux (An irradiance measurement over the wavelength interval of operation for the lidar would provide a useful indication of potential background light and actual measured value shall be recorded)

— Temperature: room temperature (e.g., 23  5 °C)

— Environment conditions: relative humidity 25 %~75 %

— Test location: Laboratory or test track

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

— Mounting apparatus (any construction where the sensors are mounted stably)

— Point cloud visualization system

— Test chamber (specifications refer to Annex C.1)

— Photodiode detector (test ambient light irradiance in W/m² and the wavelength interval of the light source should be stated)

— The interfering light source (The interfering light source can be sunlight or simulated light source. If sunlight is selected, it is necessary to use a luxmeter to measure the sunlight and record it. If a simulated light source is selected, it is necessary to use a light source that is the same as the lidar spectrum (i.e., infrared spectrum), and use a photodiode detector to test the simulated light source and record it, and indicate the wavelength interval of the light source.)

Test procedure

a) Mount the DUT (the height is recommended to be 1 m);

b) Mount the interfering light at the same height as the DUT; the distance from the light to the DUT's measurement origin, denoted as d, shall be 0,5 m;

c) Record more than 100 frames of point cloud without activation of interference source; Count the total number of scan points, denoted as N;

d) Record more than 100 frames of point cloud with activated of interference source;

e) Compare the difference in point cloud between step c) and d), Count the total number of all points that are d_n m away from the original point cloud, denoted as N_FP.

NOTE d_n should be documented in report, and d_n is recommended 0,6 m.

Figure 19 — Illustration of a setup for evaluating lidar with interference from a light source

Data processing

Calculate the stability of the point cloud, expressed as a percentage, using formula (18).

A higher value of S corresponds to a better capability of resisting external interference from a light source.

Purpose

This test is intended to evaluate a lidar’s capability of identifying and filtering interstitial points.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2 (recommended < 100 lux for this test; actual measured value shall be recorded)

— Target reflectivity: … % (recommended 10 %~ 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23  5 °C)

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

— Mounting apparatus (any construction where the sensors is mounted stably)

— Point cloud visualization system

— Targets

Test procedure

a) Mount the DUT (the height is recommended to be 1 m);

b) Place the front target d m from the DUT. Place the back target 0,3 m ± 0,02 m from the front target; An overlap of the front and back targets shall exist on the path of the DUT's normal incidence;

c) Move the back target away from the DUT with a distance step of 0,1 m until the interstitial points disappear. Record the distance L between the front and back targets;

d) Adjust the distance d and repeat the test;

e) Extract the distance L where no interstitial points are visible for each distance d.

Key

1 DUT

2 targets

3 interstitial points

d distance between DUT and the front target

L distance between the front target and the rear target

Figure 20 — Illustration of a setup for testing lidar interstitial point

Data processing

a) Distance between the two targets when the illusional points disappear frame more than 80 % is recorded and evaluated in this test.

b) Definition for false positive in interstitial point test: more than d_n m away from one surface, d_n should be documented in report, and d_n is recommended 0,3 m.

Purpose

This test is intended to evaluate a lidar’s capability of minimizing the ghost points.

There are various reasons for the appearance of ghost points. For detailed causes and information on whether this test method includes them, please refer to Table 1.

Table 1 — Exemplary list of situations and their classification

a). Multiple appearance due to internal crosstalk

b). Multiple appearance due to angular ambiguities

c). Appearance at shorter distance than real due to range ambiguity

d). Detections reported behind a solid object (ringing)

e). Blooming around a highly reflective object

f). Mirror object, resulting from multi-path propagation (out of scope)

Key

<graphic></graphic> reported detection in point cloud

<graphic></graphic> reflection points at true object, not part of reported point cloud

<graphic></graphic> reported false positive detection in point cloud

<graphic></graphic> object at which reflection occurs

<graphic></graphic> representation of instrumented FOV

NOTE Ghost points are prone to appear around highly reflective targets. For more information on highly reflective targets, refer to Annex E.

Figure 21 — Illustration of ghost points typical situations

Test condition

The test shall be conducted under the following conditions. If no specific values are provided in the specification, the values can be independently selected. The selected values shall be documented alongside the test results.

— Target reflectivity: … % (recommended 90 %)

— Target dimensions: … x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23  5 °C)

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

— DUT (Can be rotated to access different area of the FOV)

— Point cloud visualization system

— Targets covered by retroreflective material (reflectivity 90 %)

Test procedure

a) Perform this test in a facility with unobstructed surroundings. (e.g., without any above-ground objects within … m of the target);

b) Mount the DUT (the height is recommended to be 1 m);

c) Place the target vertically on the ground; the distance from the target to the DUT's measurement origin, denoted as d, shall be (d_min + 0,1 m) (the target should be mounted in such a way that the centre of the target at a height is 1 m and the mounting apparatus is minimally visible);

d) Power on the DUT;

e) Move the target away from the DUT at low speed (e.g., 0,1 m/s), until the distance reaches … m;

f) Record all point cloud;

g) Calculate the number of valid points on the target;

h) Calculate the number of false positive outside the target;

i) Evaluate the number of false positive in every frame and record the maximum value;

j) Rotate DUT to different concerned angles and repeat the above process, these angles should be recorded.

NOTE 1 d_min is claimed in user manual user manual of DUT.

NOTE 2 When rotating the DUT, make sure the target is completely within the FOV.

Data processing

Calculate the false positive ratio, expressed as a percentage, using formula (19).

(19)

where

is the number of theoretical points of one frame

is the maximum number of false positives in the recorded point cloud

R is the false positive ratio

A lower value of R corresponds to a better capability of resisting ghost points.

Purpose

This test is intended to evaluate a lidar’s capability of minimizing the false positive caused by blooming.

Test condition

The following test conditions shall apply, if there is no value specified, it can be chosen independently, but the value shall be documented together with the test results:

— Ambient light: refer to 4.1.1.2 (recommended 75 klux to 100 klux for this test; actual measured value shall be recorded)

— Target reflectivity: … % (recommended 90 %, see Annex E for definitions of high-reflective targets in different countries)

— Target dimensions: … m x … m (e.g., 2 m x 2 m, 1 m x 1 m; additional target can be used and shall be documented)

— Target orientation: perpendicular

— Test location: laboratory or test track

— Environment conditions: relative humidity 25 %~75 %

— Temperature: room temperature (e.g., 23 ± 5 °C)

NOTE See Annex C for more information.

Test setup

Equipment or software to be used in the test is shown as below.

— Mounting apparatus (any construction where the sensors is mounted stably)

— Point cloud visualization system

— Targets covered by retroreflective material (reflectivity 90 %)

Test procedure

a) Perform this test in a facility with unobstructed surroundings. (e.g., without any above-ground objects within … m of the target);

b) Mount the DUT (the height is recommended to be 1 m);

c) Place the target vertically on the ground, the distance from the target to the DUT's measurement origin, denoted as d, shall be d_min+0,1 m (the target should be mounted in such a way that the centre of the target at a height is … m and the mounting apparatus is minimally visible);

d) Power on the DUT, move the target away from the DUT with a defined distance step of ...m, until no blooming appears anymore or until the distance reaches d_max;

e) For each distance, calculate the number of valid points on the target, and the number of false positive outside the edge of target;

f) Record at least 100 frames of point cloud;

g) Evaluate the number of false positive in one frame at each distance and record the maximum value.

NOTE 1 d_min and d_max is claimed in user manual user manual of DUT.

NOTE 2 The distance between the edge of the target and the surrounding items or ground must be no less than 0,5 m in step c).

Figure 22 — Illustration of a setup for testing lidar blooming

Data processing

Calculate the false positive ratio, expressed as a percentage, using formula (19).

A lower value of the false positive ratio corresponds to a better capability of resisting blooming.

NOTE Count the false positive points within n (e.g., n=2) angular resolutions outside the edge of the target as the blooming points.

1. 
   (informative)
   
   Examples of lidar applicable scenarios
   1. Applicable scenarios

Lidar as defined in this standard is applicable for exterior detection, the following is an example of potential automotive lidar installation positions.

Key

1 lidar installed on the roof of vehicle

2 lidar installed on the front windshield

3 lidar installed on the front grille

4 lidar installed on the side of the vehicle

Figure A.1 — Example of lidar installed on a vehicle

• 1. Non-applicable scenario

Lidar as defined in this standard is non-applicable for in-cockpit detection, the figure below gives an example of the corresponding situation.

Figure A.2 — Example of cabin lidar for in-cockpit detection

1. 
   (informative)
   
   Description of applicability of test items

The performance test items defined in this standard may not applicable to all types of lidar. The following table provides reference for the applicability of specific test items.

Table B.1 — Illustration of test item applicability

1. 
   (informative)
   
   Test apparatus
   1. Low reflectivity test chamber
      1. Size

To ensure accurate measurement during testing, the distance between the DUT and the wall of test laboratory shall be greater than the minimum range capability of the DUT. The length and width should be no less than 4 m, and the height should be no less than 2 m, as shown below.

Key

1 DUT

2 target

Figure C.1 — Example of test laboratory

• • 1. Covering Materials

To ensure accurate testing conditions for the lidar, the interior surfaces of the darkroom, including the walls, floor, and ceiling, shall be covered with low reflectivity materials. The reflectivity of the covering material’s surface shall not exceed 10 %.

• 1. Target

Specifies the target's dimension, reflectivity, Lambertian property, glossiness and flatness.

• • 1. Surface Characteristics of Diffuse Reflectance Targets

The diffuse reflectance targets used for testing should exhibit near-Lambertian properties, ensuring that their surface approximates an ideal diffuse reflector.

• • 1. Reflectance Requirements

The reflectance of the diffuse reflectance targets should be within ±2 % of the required reflectance specified for the test.

• • 1. Calibration of Reflectance

The reflectance of the diffuse reflectance targets shall be calibrated using a spectrometer. The calibration should encompass the spectral range of the laser wavelengths emitted by the lidar being tested.

• • 1. Calibration Validity Period

Diffuse reflectance targets shall have a valid and NIST traceable calibration when used.

• • 1. Recommended targets List

All recommended targets in current test methods are listed in the following table.

Table C.1 — Recommended targets

1. 
   (informative)
   
   Point estimation and interval estimation

Point estimation and interval estimation are two methods used in statistics to estimate population parameters.

• 1. Point estimation

Point estimation involves calculating a single numerical value from sample data to estimate a population parameter (such as mean, proportion, or variance). The result of point estimation is a specific number.

The point estimate of the mean is shown as Formula (D.1)

(D.1)

where

is number of samples

is a specific physical quantity

The point estimate of the standard deviation is shown as Formula (D.2)

(D.2)

• 1. Interval estimation

Interval estimation uses sample data to calculate a range of values, typically used to estimate the possible values of a population parameter. The result is a confidence interval that includes potential values of the parameter. The confidence interval for the standard deviation is shown as Formula (D.4). Interval estimation provides information about the reliability of the estimate, usually accompanied by a confidence level (such as 95 %), indicating the probability that the interval contains the true population parameter.

When the population standard deviation is unknown and number of data is large enough (), the confidence interval for the mean is shown as Formula (D.3)

(D.3)

where is the percentile of the Student’s t-distribution with n-1 degree of freedom

(D.4)

where

is percentile from the chi-squared distribution

is significance level (e.g., for a 95 % confidence interval, )

To comply with the general requirements of ISO standards for measurement uncertainty, the uncertainty assessment in lidar performance testing should follow the methods specified in JCGM 100:2008 (GUM).

1. 
   (informative)
   
   Highly reflective target

There is a possibility that lidar performance may be affected by highly reflective targets, as shown in the table below, which lists standards from various countries, offering their definitions of highly reflective targets for reference.

Table E.1 — Reference definitions of highly reflective targets

Bibliography

[1] ISO/TS 19130‑2:2014, Geographic information — Imagery sensor models for geopositioning — Part 2: SAR, InSAR, lidar and sonar

[2] ISO/TR 27877:2021, Statistical analysis for evaluating the precision of binary measurement methods and their results

[3] DIN SAE SPEC 91471:2023-05, Assessment Methodology for Automotive lidar Sensors. DIN Deutsches Institut für Normung e. V.: Berlin, Germany, 2023

[4] JCGM 100:2008, Evaluation of measurement data — Guide to the expression of uncertainty in measurement.